alina, thanks so much for the reporting. keep us posted, especially if anybody launches any litigation after all of this. i'm sure once they get past the being scared, they may get angry. alina machado, reporting live for us. stay tuned, my colleague wolf blitzer, will take over the helm right now. hello, i'm wolf blitzer. it's 1:00 p.m. in washington, 2:30 a.m. friday in pyongyang. wherever you're watching from around the world, thanks for joining us. the democratic presidential candidates meet in a high-stakes debate less than eight hours from now. this will be the first face-off between bernie sanders and hillary clinton since his blowout win in new hampshire. sanders hopes to maintain the momentum, while clinton is trying to hone the message and strategy.

brianna keilar is in milwaukee, wisconsin for us. the site of tonight's pbs democratic presidential debate, simulcast here on cnn. brianna, how important is this debate for both bernie sanders and hillary clinton? >> it's really going to be a crucial 95 minutes tonight, wolf. because you have this narrative in place now, coming out of bernie sanders' win in new hampshire. he's really riding high. we have seen him taking this victory lap in the last day, being very visible, going on "the view," going on "the late show," talking to reverend al sharpton. and you see hillary clinton kind of laying low in the last day, getting ready for tonight as she often does. and that just speaks to how crucial i think her campaign views tonight be. she wants to turn this narrative around so such a big defeat in new hampshire. and really i think what we're going to see, talking to sources is hillary clinton trying to draw contrasts between herself and between bernie sanders. that she's going to try to cast him as someone who is really

walking away from president oba obama. i think we're going to see that distinction. and then i think we're also going to see bernie sanders, as well as hillary clinton, trying to push forward towards nevada and south carolina. two very different electorates that we're going to be seeing moving forward as opposed to what we saw in iowa and new hampshire, wolf. >> the race clearly has changed since sanders -- i think it's fair to say had a land slide win over her in new hampshire, right? >> that's right. because -- right now, you know, they're at a bit of a tie and he's seen as a very legitimate contender against hillary clinton. and she's very much in a way we haven't seen, back on her heels more than before. but i think what we're also going to be seeing moving forward is a race that is also changing. the sanders campaign knows that it has a lot of difficulties ahead of it. and that's namely because of the hispanic vote in nevada, which will have its democratic caucuses next. and then because of the

african-american vote in south carolina, which will hold its primary later this month. hillary clinton is heads and tails above bernie sanders, with particularly black voters. that is something that bernie sanders is going to try to be tailoring his economic message so that he can attract more black support. it's also, even just today, wolf, you saw the congressional black caucus pac endorse hillary clinton. and this is just indicative of how well she is doing with black voters, with prominent african-americans and just how much ground in this area bernie sanders has to make up. >> good point. all right, brianna, thanks very much. brianna keilar in milwaukee for us. more insight now, the debate strategy for both hillary clinton and bernie sanders. going into the debate tonight. joining us, our cnn political director, david shallian, executive editor mark press ton, and david gergen. david, she's got -- she's a very good debater. but do you think her strategy

has evolved, shall we say, as a result of her defeat in new hampshire, leading into tonight's debate? >> well, there's no doubt that she wanted to sort of regroup and i think sharpen her contrast with sanders. i think that's what i'm expecting to see and sort of what i'm looking for. because i think she thinks that he is starting to win the debate of ideas with her, and that is unacceptable to her. so i think what you're going to see is a real investigation, if you will, or exploration of his record compared to her record, so that she can try to show democratic voters that she's had progressive ideas in the very same way that he has. that's her mission. >> the exit polls in new hampshire show she did not do well among the younger voters, men and women, for that matter. she's got to be -- she's got to broaden her appeal, shall we say. >> she does have to broaden her appeal, and the the sanders campaign has done a wonderful job, smart, strategic job of bringing younger voters in. the divide is, younger voters don't see this as this once in a

lifetime opportunity to have a woman elected president. older women do, and that's why she does so well. but talking to a top official in the clinton campaign, just an hour ago, asks about this. and they said listen, we're not going to make the same mistake we did in new hampshire. new hampshire was what it was. we're going to make a play for younger women, but not just white younger women. meaning they are going to try to target african-american women and these are their points. guns -- they're going to try to highlight sanders' gun record. they're also going to point out that sanders is critical of the first black president in the united states. and hammer home on the idea that bernie sanders wants to dismantle the affordable care act. >> that's interesting stuff. is hillary clinton herself going to make those points or her surrogates and aides? >> i believe it's going to be her surrogates and aides. but tonight on that debate stage i think she's going to talk about guns, and she will in a nutshell sort of way talk about the difference with barack obama and sanders. >> she made all three of those points that you just laid out in the south carolina debate with

bernie sanders. i should note. and it still didn't resonate. >> david gergen, sanders is expecting more attacks from clinton and supporters. listen to what he said tuesday night after winning decisively in new hampshire. >> i have been criticized during this campaign for many, many things. every single day, that's okay. that's all right. they're throwing everything at me, except the kitchen sink, and i have the feeling that kitchen sink is coming pretty soon, as well. >> i think he's going to get a lot more scrutiny now that he's doing so well in these primaries, right? >> yes, he will. wolf, i question the notion that she would benefit from going after him and drawing all these divisions. she doesn't need to tear sanders down so much as she needs to build hillary clinton up. in the eyes of especially the

eyes of the -- of the young. if she -- she needs to give voice now to millennials, especially young women. she needs to give voice to black americans, and she needs to give voice to the working-class americans. and all of those people are not resonating so far with the kind of message that she has projected. she is the most experienced person to run for the presidency in a long time. but she -- that makes her the establishment. that makes her the walking establishment, and she's now got to convince these people -- a lot of questions of the younger. even questions starting to pop up in the black community about her and whether they'll support her. she needs to bring those people to her and inspire them. i don't think it's as important to tear down sanders as it is to inspire and build herself up. >> one of her main points, david, you know, he's got revolutionary ideas, free tuition, all this stuff. it's not really practical in the real world of washington, d.c. you're not going to get that passed. she's going to be more practical, right? >> that is -- that has been one

of her message points. i don't know that that has been a winning resident message for where the electorate is right now. to david gergen's point, that's why she has to find a new way to talk about her own progressive credentials and set the bar of what still can be achieved. but if you just come out, as she has, and said but i can get this done, when you look at the exit polls, that's not necessarily the highest priority for democratic voters right now. >> well, and one of the things she does, too, when i have the credentials. when i graduated college in the '70s, this is what i did in the '70s, guess what, a whole new generation looks at the '70s as eons and eons ago. she has to do a better job of conveying the positiveness but need a way to take him down a few notches. they have to take him off of this slide or rather this ascension he has going on right now. >> very quickly, david gergen, she may try to use foreign policy which supposedly is her great strength and maybe his

weakness in this debate tonight. >> i would think she would. and i think there she can be -- she's very knowledgeable. i think she just needs to keep it brief, don't get too far down in the weeds and give people a clear understanding of where is shall going. this campaign is too much about the past, has to be more about the future. and here's where i think we should be going, here's the kind of world i think we should be building together. >> all right, guys, stabbed by. tonight's cnn will be simulcasting the pbs news hour and debate live from milwaukee, wisconsin. that's at 9:00 p.m. eastern. you'll find it right here on cnn. and for our viewers in the united states, you can also find it on your local pbs stations. hillary clinton is getting a big boost as she battles bernie sanders for her african-american voters, and south carolina and across the south. today the congressional black caucus' political action committee announced it was endorsing her by a near-unanimous vote. listen to this. >> so you judge a person by

their results. and there is no question that the person that has obtained the most results and benefits for communities of color and everyone in america, in my opinion. but especially getting democrats elected, there's not even close. it's not even close! it's hillary clinton. >> strong endorsement comes a few days before hillary clinton set to meet with a group of civil rights leaders in new york. among the people attending that meeting next week will be marc mori morial, president of the urban league. thanks very much for joining us. >> thanks for having me. >> u.s. president of the national urban league. i take it you're not endorsing anyone, at least not right now. is that right? >> we do not. we have no plans to endorse anyone. so i'm in a great position to talk about this campaign, and talk about what's important to our community and wolf, as you mentioned, in your tease, we will be hosting hillary clinton

in a civil rights briefing next tuesday, and we have offered the same briefing to all candidates, republican and democrat. we are in conversations with the sanders campaign about scheduling a briefing with him. the clinton campaign is first, because they were the first to respond to our investigation. >> the -- i guess the question is this. as president of the national urban league, i assume you've worked closely with bill and hillary clinton over the years. has bernie sanders been directly involved in the issues that you're promoting as president of the national urban league? >> so this is -- this is true when it comes to bernie sanders. my first opportunity to meet bernie sanders is when he attended the national urban league's 2015 conference in ft. lauderdale, florida. but bernie sanders and i did have a telephone conversation about two or three years ago when he called me to talk about a youth employment bill that he was introducing. but certainly there's been a long standing i think

relationship with hillary clinton, with bill clinton, and many leaders of cities and many leaders in the urban community and many african-american leaders. so the track record is there. i think with bernie sanders as an acknowledgment that he's been a proponent of progressive causes. but i think he also starts out in a place where people are just getting to know him for the first time. >> in the african-american community, because there is a very small african-american community in his home state of vermont. small african-american community in iowa, where the caucuses took place. but among democrats, more than half expected to vote among the primary in south carolina, african-american. so that will be critical moving forward, right? >> no doubt, wolf. and i think what we have seen is that only 4% of the delegates on the democratic side have been determined. and now the landscape ahead will certainly be diverse states, states with african-american,

hispanic, blue collar democrats, democrats who are middle and higher income. a much more if you will, diverse mix of gumbo, if you will, of people and that's what's ahead. and so this will be a test for these candidates, the ability to build within the democratic, if you will, community, a coalition of supporters. and i think south carolina is one state, and many states ahead where the african-american community is going to be critical. the question really is, who offers a relationship with the african-american community when it comes to the idea of governing? and so you've got to not only look at what candidates are saying in the context of this race, you've also got to look at where they have stood and where they have led on issues historically. and one of the things i think is important is whether bernie sanders and hillary clinton -- and this is an important question for them.

what have their staffs, what have their senior leadership teams looked like, not only in their campaign, but historically, as they have been in public life. so that's an area of inquiry. where they have been on legislative issues where they've had to cast votes. and what positions are important to them? what is their vision for the african-american community to be a part of a governing coalition? should they become the nominee and should they become president of the united states. those are the very important questions i think that people are going to be talking about as they look at the upcoming, if you will, primaries ahead. >> marc morial, president of the national urban league. thanks very much for joining us. >> always, wolf. thank you. up next, the republican candidates also on the campaign trail today and on the attack. you're looking at live pictures of jeb bush in south carolina. we'll talk about how jeb bush, mariah carey, marco rubio, are criticizing their rivals. and a look inside the war-torn

city of syria. in aleppo. we'll be joined live from syria. a lot more coming up. ou have moe rheumatoid arthritis like me, and you're talking to your rheumatologist about a biologic... this is humira. this is humira helping to relieve my pain and protect my joints from further damage. this is humira giving me new perspective. doctors have been prescribing humira for ten years. humira works for many adults. it targets and helps to block a specific source of inflammation that contributes to ra symptoms. humira can lower your ability to fight infections, including tuberculosis. serious, sometimes fatal infections and cancers, including lymphoma, have happened, as have blood, liver and nervous system problems, serious allergic reactions, and new or worsening heart failure. before treatment get tested for tb. tell your doctor if you've been to areas where certain fungal infections are common, and if you've had tb, hepatitis b, are prone to infections, or have flu-like symptoms or sores.

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presidential candidates get set to face off in wisconsin and n a key debate later tonight, that is being simulcast on cnn and the republicans are laser-focused on south carolina. take a look at the map. ted cruz, john kasich, jeb bush, marco rubio and dr. ben carson. they all have about a dozen events between them. in the course of today. and then there is donald trump, fresh off a rally in south carolina last night. there was a huge crowd there. he's flying solo to louisiana today, where he'll rally voters tonight in baton rouge in advance of the louisiana contest next month. and in a conversation with republican presidential candidate, marco rubio, marco rubio told me he's confident about next week's south carolina primary. also, wasted no time slamming jeb bush and his experience. >> jeb is trying to say whatever he can to get an advantage. the fact of the matter, jeb has no foreign policy experience. none. he just has no foreign policy experience, and he was governor a long time ago. the world has changed a lot in

the last ten years and foreign policy has changed a lot in the last five years. and no one on that stage has more experience or has shown better judgment or a better understanding of the national security threats before this country than i have. governor bush spent a lot of money in new hampshire, and finished basically tied with me and ted cruz, despite spending a record amount there. we'll see how things play out. i feel good about our team in south carolina. >> right now, take a look at this. you're looking at live pictures of what is the first of three planned campaign stops for jeb bush in florence, south carolina before he continues to sumpter and columbia. they wished him a happy birthday. he's 63 years old today. remember, we're just nine days away from the first in the south primary, and jeb bush is taking direct aim not only at some of the republicans, but especially against the front runner right now, donald trump. let's go to victor blackwell, he's covering the bush campaign

for us. joining us live from myrtle beach in south carolina. victor, has jeb bush responded directly to what marco rubio told me yesterday, that the guy -- rubio says has really no foreign policy experience? >> yeah, wolf. we have put that question directly to the campaign's communication director, tim miller, and he offered no response. because as you said, they're putting it straight to donald trump. but look, the governor has said that this is a national security election here in south carolina. and that's the argument they're making. lindsey graham, his former opponent, now supporter, south carolina senator. his introduction is based specifically on national security. what the governor is talking about right now is national security. what did they hand out here at this location? not flyers about an economic message or social justice message. but specifically about national security. and, again, they're taking it to donald trump, saying that he is not prepared, he's not a serious candidate. listen to what the governor said

yesterday at a rally at a bar, actually, near myrtle beach about donald trump, as he's compared to president obama. >> can you imagine donald trump as president of the united states, where he spends his time pushing people down to make himself the big dog on the stage? we will be worse off than we are now, and we're really bad off right now. >> remember i called him a low-energy person? he's a low-energy person. i said -- no, i said he's a stiff. and i said if he was in the private sec to, he wouldn't be able to get a job. other than that, i think he's excellent. this is going to be our president. >> and wolf, there was one person at that event near myrtle beach who said to governor bush, listen, here you're confident, you're calm, you're relaxed. you're not that person in the debates. why? governor bush then said, watch me this saturday. in fact, vote for me next saturday. but he is suggesting there will be a change continuing this ramped up attack on donald trump. >> victor blackwell, covering

jeb bush down there. thanks, victor, very much for that report. governor kasich, he's also in south carolina right now. he is speaking at a town hall in myrtle beach. you see him there. they're all going out, they're all campaigning. not very far down the road, the south carolina contest, which will be critical on the democratic and republican side. and this just coming in to cnn. donald trump now settling. the presidential candidate has settled his differences with univision. univision dropped the pageants and protest of trump's comments about illegal immigrants in his campaign kickoff speech when he said mexico was sending, among others, some of the worst to the united states. trump sued. now they have settled. the terms of that settlement, though, they are being kept confidential. up next, more news happening right now. russia and the united states squaring off directly over syria. accusations flying as the bombs fall. we're going to sort out what's going on.

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here i come! can't find you anywhere! don't settle for u-verse. x1 from xfinity will change the way you experience tv. the city of aleppo is now a casualty of war. in the fight against isis, both the u.s. and russia are carrying out air strikes, now trading accusations against one another of exacerbating the situation. let's go to our pentagon correspondent, barbara starr. barbara, the u.s. is brushing off russian claims that two american war planes bombed aleppo. what sparked this latest uproar? >> the pentagon says they don't know, they have seen the russians do this before, making statements about u.s. military operations that the u.s. clearly

says are not true. so why is the u.s. saying this one is not true? because there are no isis targets in aleppo. the u.s. mission is to bomb isis. isis is not in aleppo. who is in aleppo are syrian civilians and anti regime opponents. opponents of bashir al assad, the very targets that the russians have been bombing for some months now. so the u.s. says it's absolutely not u.s. war planes, and that the russians they say simply are not telling the truth. the russians say there were two u.s. war planes bombing in aleppo. wolf? >> are there any planes for the russians to cut down the number of sorties? >> at this points the u.s. doesn't see it. there are these ongoing peace talks that are very difficult right now and don't really appear to be headed anywhere the russians have been calling for some sort of cease fire. but when you look at what is happening in aleppo, the city in

the last several days has become surrounded. surrounded due to russian air strikes, regime forces, iranian backed shia militias, hundreds of thousands of people at risk, really just barely subsisting in this city. the russians engaging in some -- at some points in more than 100 air strikes in a 24-hour period, according to u.s. estimates. so no indication yet that the russians for now have any plan to back off. wolf? >> all right, barbara, thank you. barbara starr at the penned gone. with bombs raining down, shells piercing the landscape, getting in and out of the city of aleppo can be deadly. cnn's fred pleitgen is the only international journalist there where syrian forces are battling rebels. >> reporter: years of urban combat have laid waste to the old town. snipers scan the terrain for possible movement on the other side. we're right on the front line of

the syrian government's offensive against the opposit n opposition. and the soldiers here tell us they still frequently see rebels on the other side, but they also say they often pick them off from the snipers' nest. this soldier tells me, morale has never been higher. thanks to god, everything here is under control, he says. our fingers are on the triggers, ready to destroy the rebels. bashir al assad's forces have made major gains in the aleppo area in recent weeks, while the opposition rebels say they're simply being slaughtered. but for years, this battlefield was in a stalemate. the front line right around the ancient citadel. as russian war planes whoever overhead, the commander knows who to thank for the new-found mom momentum. it's only a matter of months until we win, he says, thanks to the russian support flown from the syrian air field, we will defeat the rebels once and for all. aleppo was syria's largest and

one of its most historic towns. tourists from all over the world used to flock to the old town before it was engulfed by syria's brutal civil war. the old town of aleppo is a world heritage site. some of these buildings are hundreds if not thousands of years old. and as you can see, most have been completely destroyed and burned out. but now assad's troops believe they are on the verge of a decisive victory. the commander warns the u.s. not to interfere. we are steadfast, he says. you cannot defeat the syrian army, because we are determined to win and we're loyal to president assad. amid this divided and destroyed city, syrian government forces believe they're dealing a crushing blow to the opposition, one that could end this five-year civil war that's destroyed so much more than just the landscape. >> and our senior international correspondent, fred polite again again, is joining us now, back in damascus.

fred, the syrian government's strategy right now to take aleppo, what else can you share with us about that? >> reporter: well, i mean, it certainly is the case a lot of what barbara was talking about. you could see that on the ground. you can see the fact that the syrian military is attempting to encircle aleppo to the places where the opposition holds sway at this point. they want to cut that off. they believe they have already largely done that, but they still want to fortify their positions even more. i was also able to go, wolf, to the north of aleppo and the area near the turkish border. and the syrian military there says it wants to advance towards the turkish border and get to the turkish border to make sure rebels inside aleppo can't get any more supplies. the other thing that really stood out, wolf, was the major presence there and the sway you saw there of hezbollah and of iran, as well. there is iranian flags on a lot of the buildings. there's pictures of iran's supreme leader. there's also pictures of the

leader of hezbollah, as well. if you talk to syrian soldiers, they will tell you that it was indeed the russian air force that has made a major difference on the battlefield. and they say it's not just the air strikes. it's also the fact that they're getting aerial intelligence from drones and the russians as well, that's making their artillery fire more accurate also. and that's something they say they simply haven't had in the past. so it's certainly the case that hezbollah, iran and russia, the syrians do acknowledge they played a major role in the offensive that's going on right now. >> and who is helping the rebels? >> reporter: well, the rebels at this point in time, not getting very much help at all. i mean, they are holed up mostly in the old town of aleppo. and it's interesting also because you have various rebel factions, some at odds with each other. the commanders told me you have more moderate factions of the army and hard line factions like the al qaeda wing of syria, called al-nusra.

so it's very difficult for the rebels to put up the unified front, and also at this point in time, very difficult also for them to get supplies, for instance, inside aleppo. in the area of turkish border, that is something different as well. they could probably still get supplies through there. but, of course, the situation for them, a lot more difficult than it has been in the past. and the government, along with russian air power, is continuing to press that offensive. we could hear a lot of thuds from bombs being dropped. we could hear a lot of air strikes, we could hear a lot of fire, especially in the night when we're in aleppo so youca really see how the rebels in that area very much on the defensive at this point in time, wolf. >> fred pleitgen doing exclusive reporting for us. back in damascus now, was on the outskirts of aleppo. still ahead, north korea executes a top military chief, sparking new speculation about kim jong-un's stability as control of the military forces in north korea. we're about to take a much

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the reign of extreme terror, some are describing senior north korean officials by the leader kim jong-un. now we're hearing the chief of staff is dead. it's believed he was executed from misuse of authority and trees treason. at least 80 top officials have now been killed on kim's orders. to talk about this and more, we're joined by the daily beast columnist. what is this latest execution of this top military official tell us about kim's control of the north korean military? >> i think it undermines the

general narrative maintained by south korea and u.s. intelligence communities that kim quickly consolidated command of the army, as well as the rest of the political system when he took over four years ago. i don't think you can maintain that now, because we have seen three four stars in the last 13 months, either killed or disappeared. and that says there is fluidity in the political situation in pyongyang. >> does he run the risk of a coup? >> i think to a certain extent he does. the north korean military understands that the regime's legitimacy depends on a kim at the top. but nonetheless, this particular kim has taken away their control of money, exports. and so that is a big deal. plus also he's put party functionaries in key military posts. and along the way, he's killed military officers which means that everyone knows they're playing for keeps. so in a situation where a senior officer thinks he's being targeted, he has very little to

lose to go against kim jong-un. so one of these days, i think that we will see the military try to move against kim. >> he's also, ken, ratcheting up tensions. last month with the nuclear test, the test of a ballistic missile. south korea suspending operations at the industrial complex inside north korea, not far from the border. today the north announced it would expel all the south koreans from the facility. this is usually a bellweher for relations on the korean peninsula. and i suspect this deterioration is going to escalate. >> you know, it certainly will. because the industrial complex, very important for the north koreans. you have about 54,000 north koreans employed there. there's been an average of about $90 million a year in the last three or four years. $515 million since it was opened in 2004. so this is material for the north koreans. and this point, the pyongyang

realizes that because there's been what it considers to be such an affront to the authority of kim jong-un by south korea, by closing the zone, they've got to do something. you know, we saw six months what happens when you have some minor incidents in the demilitarized zone which separates the two koreas. this is a much bigger deal so therefore the consequences, i think, are going to be much larger. >> yeah, let's not forget nearly 1 million north korean troops not far from the dmz, nearly 30,000 american troops right in between, along the dmz, as well. a very, very tense situation that we're monitoring right now. gordon chang, thanks very much. just ahead, countdown to a political showdown. bernie sanders and hillary clinton may meet in a major debate tonight. our political panel getting ready to examine what's at stake for both of these candidates. that happens when we come back.

live pictures coming in right now of senator marco rubio, in south carolina, myrtle beach, holding a town hall. all of the democratic and

republican candidates getting ready for the south carolina contest. we're counting down to tonight's democratic presidential debate between bernie sanders and senator clinton. sanders trying to build on the momentum from his big win in new hampshire. hillary clinton is trying to rebound from her loss. for more, let's bring in cnn political commentator and democratic strategist, maria cardona and political strategist jonathan at this seeni, author of "the essential: bernie sanders and his vision for america." he supports bernie sanders. jonathan, what's at stake in the debate tonight? >> well, i think every time i'm asked that, i say the same thing. for bernie, it's pretty straight forward. he wants to be known to more americans across the country. he doesn't have to look around for slogans or figure out what the next poll-tested slogan should be. he's very straight forward in terms of the principle he's held for 30, 40 years and wants to explain how he wants to change the rigged economy and corruption in washington.

>> hillary clinton has to come back from the stunning defeat in new hampshire. what does she need to do tonight? >> i think she needs to focus on her message of actually trying to get things done. this is one thing that senator sanders has not been able to answer in any of the debates or any of the interviews he's done, which is everything that he's talking about sounds great. but how is he actually going to pay for it? hillary clinton does all of those things, works for proposals that will help middle class families that will help african-americans, latinos, immigrants. but she does it in a way that she pays for it all. so i think facts matter. we are democrats, facts should matter to us would draw indepen

in the way an establishment candidate, goldman sachs, $225,000 for one speech, $600,000 for three speeches. republicans $150 million by cnn's count for speaking fees, large banks, all sorts of drug companies, insurance companies. these are the people that actually corrupt the process in america. and i think that's really what bernie will talk about and that's what -- he would be the strongest candidate in the fall, because americans are sick of the corruption in politics. and i think that's true of both parties. bernie has polled stronger against both trump and rubio. >> maria, you support hillary, go ahead. >> i think that tonight is going to underscore why democrats and a lot of those independents that bernie sanders is bringing in should support hillary clinton. she has focused on how to build upon all of the progress that

hillary clinton has given our country. he has a superpac of nurses supporting him and running ads on his behalf. the second part is they love to talk about how hillary clinton is not credible when it comes to talking about issues of criminal reform, of mass incarceration, because she was the wife of the president who signed the 1994 crime bill into law. bernie sanders voted for that bill, campaigned on it, campaigned as being tough on crime and talked about -- >> all right, very quickly, jonathan. >> -- would be hurt by it -- >> if the debate comes down between the support that hillary clinton gets from goldman sachs, she actually did win the goldman sachs base in new hampshire, the only income level she won, above $150,000, versus working nurse who are the core in the hospital, the way people are cared for. we would win that hands down. >> you can't win on purity if

you're not pure -- >> we can run on nurses versus goldman sachs, that's an easy debate. >> she's worked for working class people all her adult life. >> nurses versus goldman sachs, slam dunk. >> working class people, working class people. >> thank you very much. >> thank you, whole. >> cnn will be simulcasting the pbs "newshour," live, right here on cnn. for our viewers in the united states, you can also find it on your local pbs station. we'll be right back. caring for someone with alzheimer's means

i am a lot of things. i am his guardian. i am his voice. so i asked about adding once-daily namenda xr to his current treatment for moderate to severe alzheimer's. it works differently. when added to another alzheimer's treatment, it may improve overall function and cognition. and may slow the worsening of symptoms for a while. vo: namenda xr doesn't change how the disease progresses. it shouldn't be taken by anyone allergic to memantine, or who's had a bad reaction to namenda xr or its ingredients. before starting treatment, tell their doctor if they have, or ever had, a seizure disorder, difficulty passing urine, liver, kidney or bladder problems, and about medications they're taking. certain medications, changes in diet, or medical conditions may affect the amount of namenda xr in the body and may increase side effects. the most common side effects are headache, diarrhea, and dizziness. all my life, he's protected me. now i am giving back. ask their doctor about once-daily namenda xr and learn about a free trial offer at namendaxr.com.

scott kelly is coming home from space after the longest stint in orbit of any american astronaut in history. today marks 321 days since structural kelly and his crew launched from kazakhstan to the international space station. in his career, 500 days in

space. this latest mission was designed to research the effects of long-term space travel on the human body. joining us now is our chief medical correspondent dr. sanjay gupta. you just spoke with scott kelly after, what, almost a year in orbit. what did he say to you? >> well, he's got a lot to say as you might imagine, wolf. just amazing, people that talk to him like that. you know, he's part of a twin study. he's got his twin brother back on earth. mark kelly, a lot of people know mark kelly, gabby gifford's house, they're comparing the twins. trying to determine how does aging take place differently. what is the impact on the body, the changes, the heart, fluid changes. he talked about how he keeps himself occupied up in the space station as well. it's really curious, you always see those amazing images of earth from the international space station and i wanted to ask him almost from a medical perspective when he looks at earth, how does it look, does it look healthy, does it look sick,

are there areas for improvement. >> certain parts of the world at times that you don't expect or other, you know, weather conditions. when you look at the, you know, atmosphere, i wouldn't say it looks -- the thin veil of the atmosphere on the limb of the earth, wouldn't say it looks unhealthy, but it definitely looks very, very fragile. and, you know, just kind of like this thin film. so it looks like something that we definitely need to take care of. >> just interesting, wolf, i mean, he's got this very, very unique view. this vantage point of that. he described pollution in certain places of the earth. these weather patterns, as you heard him say and also the thinning of the atmosphere. almost like the thinning of someone's hair on someone's head although this is obviously more serious, wolf. >> did he mention any side effects he has already noticed from being in space for almost a year? >> one of the big one, it's something he's dealt with before

as well as other astronauts, is the impact on vision. it's interesting, in some ways, despite the fact that overall time is moving more slowly, very minuscule difference but moving more slowly for him. he, in fact, his body is aging more quickly. so the eyes were a big one that was noticeable for him. but also the lack of gravitational pull on his body, on his bones, makes his bones more brittle. not as dense. there's fluid shifts around his heart. there's all these things he may not be fully cognizant of but he's being matteasured every da and he's having those measurements, again, compared to his twin brother who's living on the earth. >> are they fraternity or identical twins? >> they're identical twins. >> amazing. >> a rare situation, both astronauts, identical twins, this rare opportunity to study them. what this is really about is mars, what it's really about.

it takes about nine months to get to mars. just showing you can be in a craft for that long. obviously, his mission is coming to an end. if you were gooding to mar, his mission would just be starting. >> all right, sanjay, excellent report. more coming up in our 5:00 p.m. eastern hour as well. that's it for me. thanks for watching. the news continues next on cnn. wolf blitzer, thank you, my friend. great to be with all of you on this thursday. i'm brooke baldwin. you're of course watching cnn and you will definitely want to be watching at 9:00 p.m. eastern tonight where hillary clinton will get her first face-to-face with bernie sanders after he beat her in the new hampshire primary earlier this week. we are simulcasting that democratic debate on pbs. as clinton prepares to seize her chance to derail