charting the next frontiers of of humankind in space. you can find more on aljazeera.com. on the front page, it's super tuesday in the u.s. we are going to make america great again, greater than ever before. >> they've been after me for 25 years and i'm still standing! >> it is super tuesday, the front runners look to lock in the nomination in the race to the white house. >> the candidates are in a fierce fight for delegates from the accident. we are live with what's at stake there. apple versus the f.b.i., two faceoff at a congressional

hearing today as the debate over national security and privacy intensifies. this is aljazeera america live from new york city, i'm stephanie sy, millions of americans have all right started casting their ballots on super tuesday. a a few hours ago, bernie sanders voted in vermont and he talked his campaign's goals. >> what i have said from day one is that our campaign does well when millions of people stand up and fight back for social justice, for economic justice, for environmental sanity. i am confident that if there is a large voter turnout today across this country, we are going to do well. if not, we are probably going to be struggling. >> today could be a potential

game changer for him and the for the republicans. there are hundreds of delegates at stake, the dems are vying for 865 in 11 states and american so mow i can't, the republicans for 595 delegates today. jonathan martin is following developments in alabama but we begin with heidi zhou castro in san antonio, the accident, a pivotal state. we are going to see more delegates awarded there than any other state in the country. >> immigration is always a big topic here in the accident with that senator ted cruz addressing it as he campaigned in dallas yesterday, taking aim in a 2013 senate plan to reform immigration that has him widely unpopular among conservatives because it includes a pathway to citizenship.

cruz being a confidenter of that legislation and attacking donald trump for making campaign donations to some of the plan's supporters. texas has 155 delegates on the republican side, 252 on the democrats, but it is notable to say texas is not a winner take all state, rather those delegates will be divided among counties, so the candidates can hope to pick up handfuls of delegates at a time, plans to crisscross the state visiting various communities. >> polls have been open there almost for a few hours now. texas is a crucial test for the texan in the race, ted cruz. what's at stake for him? >> most analysts are saying that this is really the state to win for ted cruz and a big win at that because of the delegate count in order for him to make a dent against donald trump, but the polls are showing ted cruz

is in trouble even here in his home state of texas, showing a 3% lead over trump and marco rubio trailing a distant third. ted cruz is still a favorite here among those established conservative texans who always vote, but the unknown factor is how many new voters can donald trump bring into this election. i know by attending his rallies, there's been more enthusiasm than ted cruz and he is a threat to the cruz campaign. >> hillary clinton leads sanders in texas and most of the south. how big a prize would that state be for her? >> that's right, she is leading her in the accident over bernie sanders by 21 points, a sizeable lead. she hopes to deliver the same sweeping win against sander as she did in south carolina. doing that, she is trying to tap into the minority vote in texas, namely latino voters and

reminding them of her work in the 1970's of registering hispanic routers and deploying her husband, bill clinton who chris crossed the state yesterday in her behalf. >> heidi, thanks. i went ahead to another southern state now, alabama where jonathan martin is living in birmingham. good morning, what kind of turnout is expect, are you seeing and who is leading in the polls? >> good morning to you, stephanie. polls have been open for an hour here. we are in birmingham this morning. overall turnout expect to be 40%, pretty high according to many officials here, considering there aren't a lot of other big state races drawing voters to the polls. alabama expected to be a bigger player this year. in previous super tuesday election, alabama was not a part of it, but this past year, the legislature voted to move alabama's primary up to super tuesday. you've seen more focus on this

state, candidates stopping by and pending money on advertising. let's look at the polls on the republican side, donald trump really with a commanding lead, most of the polls showing him now over 40% of the vote. really the thing to watch here in alabama will be who can come out in second, because rubio and cruz both running neck and neck. they will see if they can win. a large part of the electorate in alabama is made up of african-americans. hillary clinton has been talking directly to african-american voters, hoping to pick up supporters just like she saw in south carolina. >> that's important for her in general in the south. voters in alabama and several southern states are dealing with a stricter voter i.d. requirement we've been reporting on a lot here at al jazeera.

what is being said on both sides about this requirement? >> a lot of talk about this and people watching to see how this will impact voter turnout. it's specifically here in states like alabama and georgia. they also have something called their proof of sit accept ship laws. in addition to the regular voter i.d. laws, you have to have a birth certificate or license for a passport and again, the feeling from at least the critics is that that disenfranchises a lot of voters, specifically minorities. >> 50 years after the voting rights act and we're again suppressing the rights of black voters in alabama. >> we will go to people's houses to have their picture made if they don't have a photo i.d. in the state of alabama. we're not ever going to do anything to keep the people in the state of alabama from voting. >> a lot of eyes on the issue. we'll see from the totals

tonight the effect it has had. >> speaking of the south and the southern voting block we are talking about today, collectively, how many delegates are we talking about? >> we're talking about a large number. you know, individually, a lot of these states like alabama don't have a ton of delegates, alabama has 50, on the democratic side, it has 60, but when you add up what they all call the s.e.c. face, out of the southeastern conference in college sports is what people refer to it as, there are a large number of delegates, really more than 250 on each side, because you have georgia voting to do, alabama, arkansas, oklahoma, so really that's why this deep south region is seen as important in this election today. jonathan, thank you so much. we are joined now by lincoln mitchell, the national correspondent for the new york observer. lincoln, thank you for being

with us. >> my pleasure. >> you've covered these before. what makes this super tuesday different than others in recent memory? >> well, on the republican side, obviously that makes a difference is there is the front runner who is poised to do really well today and everyone is desperately figuring out how to stop that person. that is very different. the guy who may welcome in second today with delegates is also somebody who everyone in the republican establishment is trying to stop. >> you are talking about ted cruz. >> the leadership hasn't figured out who they hate more. they have landed on marco rubio, probably the strongest general election candidate. trump has twice rubio's support, so he's not a real factor. the hope is to somehow get from here to that rare unicorn of a

brokered convention. on the democratic side, this is the first time where a candidate in what was a competitive race is poised to really break it open on super tuesday. super tuesday, the last competitive democratic primary, clinton and obama were neck and neck. 1988, al gore and jesse jackson were neck and neck. this is a little different dynamic with regards to hillary clinton. >> clinton does seem to be widening her lead over the bernie sanders, in south carolina winning by double digits. he has continued to raise a lot of money from individual donors. he raised as much money last month as he that during his whole campaign. what is the must ore win for sanders today? he's going to win vermont, what about massachusetts, colorado. >> what is the delegate count that he needs, i'm putting that at 45%. if he gets 45%, he's in fine

shape, less than 40, i think he says kind of out of it. minnesota, massachusetts and colorado, now he needs to win at least one of those. of those three, the most important by far is massachusetts. it's a neighboring state, so should be the easiest, although elizabeth warren who is a kindred spirit that stayed out of the race and hillary clinton has been working hard there. if she beats him there, that is not good for bernie sanders, but minnesota is a state with a progressive democratic party. if we look at the s.e.c. and i am not a big college sports fan. >> me either. >> there is georgia and alabama, deep south states, huge african-american vote. oklahoma, tennessee. >> tennessee. >> and arkansas are technically southern states. they were part of the old confederacy if that means something. much lower african-american

vote. if hillary beats him in tennessee and oklahoma, she is doing it with largely white support, showing she is winning across racial lines. >> is that a factor in virginia, as well? let's talk about texas, cruz should win texas. the latest poll shows cruz 35%, trump 32%, within the margin of error. they are basically neck and neck. >> who has to win the accident, if he doesn't win texas, this campaign is effectively over. you can't get elected in a tough state, tough primary to the u.s. senate and four years later not carry it in the presidential primary. >> how much does he need to win it by? >> he has to win it by one vote to have bragging rights. the centrist populist nativist course he's taking is appealing

very broadly to the large -- obviously not to democrats, they are not voting in this thing, but to places we think of as very copp. it shows there is a fact you aring of what it means ton conservative today. >> several southern states in super tuesday, looking ahead to march fib, getting into the farther northern part of the country. do you anticipate any of the republican candidate dates bowing out? don't they want to see what happens with trump when he gets further rest? >> i don't anticipate anyone getting out. the most obvious person is carson. he seems to be having fun if one can tell with him. in fairness to john kasich, that makes sense. if he can win ohio, he takes some delegates off the board for donald trump which others have been unable to do so far. approaching mark 15, what does marco rubio do. he gets to be in a similar situation but more extreme

because florida is a winner take all state. if he goes to florida and loses it, what does that do with his standing in the party and florida? cruz and rubio have a future. >> these are sitting senators. >> and young, both under 50. they should be thinking what can i do to position myself for 2020. losing your home state to donald trump may not be the best way to start that pros. >> that would not look good. >> mitchell, thank you. it's exciting. it's an exciting day. >> it's a lot of fun. >> this morning, we are getting a chance to see the final batch of hillary clinton's private emails from her time as secretary of state, roughly 2900 remaining pages of documents were released monday. they show policy conflicts her team had with counterparts at the white house. 2100 of the more than 50,000 emails have now been marked classified years after she sent them. protestors at a donald trump rally, protestors interrupted

his speech. there were about five incident republicans, including one but a young female protestor who trump called out. >> are you from mexico? are you from mexico? huh? are you smack in the middle of my punch line! >> that was not the only issue at that rally in virginia. this morning, the secret service is investigating what happened when one of its agents scuffled with a time magazine photographer. >> it started when black lives matter protestors interrupted donald trump's speech. >> get them out of here, please. >> that's when time magazine photographer chris morris stepped outside of the designated press area to get a better shot. watch the highlighted area. morris is confronted by a secret service agent who puts his hands around morris' neck and throws him to the floor. a different angle shows morris cursing the agent before the tussle.

on the ground, morris kicks his legs and immediately begins protesting that the agent grabbed him by his neck. as agents vconverge, morris puts his hands on the agent's neck, demonstrating what the agent did for him. at that point, bradford university police took morris into custody. >> i never punched him. i never touched him. at the very end, i tried to show what he did to me and i said he choked me, so i put my hand on him and that's when i was arrested. >> charges were never filed and morris said he is not pressing charges, either. in a statement, he said i regret my role in the confrontation but the agent's response was disproportionate and unnecessarily violent. the secret service said it's local field office is working with their law enforcement partners to determine the exact circumstances that led up to this incident. time magazine has contacted the agency to express concerns about the level and nature of the agent's response.

a showdown over security, apple and the f.b.i. go before congress in the fight over unlocking the san bernardino's phone. president obama meets with republican senators to talk about filling the open seat on the supreme court.

i see him with makeup and it's like he's putting it on with a trowel. >> donald trump was avoiding the draft because he got hurt playing squash. >> thank god he has large ears, the biggest ears i've ever seen. >> vladimir putin, he seems to have a bro mans with. >> i have never seen any human being sweat like this guy. >> you know what they say about men with small hands. you can't trust 'em. you can't trust 'em. >> conservative political commentator said that kind of discourse is damaging to all the

candidates. >> this is not being presidential. we are watching candidates redefine what they think is being presidential when america needs more presidential behavior more now than over the last 35 years. >> you have people in the republican party saying they would not vote for trump if he became candidate. senator ben sass has become the highest ranking republican saying he would not vote for trump if he becomes the nominee. who he would would have the weight to counter trump's influence on the party? russia limbaugh, bill o'reilly? who has to call him out for it to actually make a dent at this point? >> we've been asking this question for a while, who's going to be able to call somebody out publicly and make the polls turn away. trump supporters belief if they call him out, they'll be out to get hem because he calls it like it is.

talking hatred and spreading divisiveness should not be telling it like it is. it's not the highest appeal of what the american dream is supposed to be all about. i don't think it's going to be a bun did it or people within the political party. it's going to have to be voters who say we want something higher for the following generation to be able to succeed. we cannot tolerate this. there is still a segment in america that feels comfortable allowing this type of rhetoric to be their voice. >> mcallister said as a christian, he can't support trump and won't vote for him. president obama will meet with republican leaders to discuss his plan to fill the supreme court vacancy, sitting down with mitch mcconnell and senator grassley who heads the judiciary committee. both say there will not be a vote. josh earnest said president obama wants a serious discussion

about filling the vacancy issues the supreme court is hearing arguments today and all eyes may be on clarence tomas. on monday, the justice asked a series of questions from the bench for the first time in a decade in a gun rights case. he last asked a question in february, 2006. justice tomas maintains his colleagues ask too many questions and don't let the lawyers make their arguments. >> apple and f.b.i. are taking their fight over unlocking an encrypted phone to congress today. a judge said apple does not have to unlock a phone in a separate case. ahead of the hearing, an apple executive wrote an open letter saying that he has no sympathy for terrorists but creating a back door to iphones would be too dangerous. apple has been criticized by some lawmakers but the company standing firm to not write

software that would allow the f.b.i. to hack into the phone. the government said it only wants to unlock one phone but apple said this is not about one phone. the judge took aim at a 200-year-old statute the government was using as base for its demands, the same statute the government is relying on in the san bernardino case. the justice department said it would ask a judge to review the decision and said apple expressedly agreed to access the data on an iphone as it had in similar circumstances and only changed course when it was made public by the court.

mission complete, astronaut scott kelly prepares to return to earth after a year in space.

al jazeera america. in less than 24 hours, two astronauts will return to earth for the first time in a career, american scott kelly and a russian cosmonaut will return. we have more on what will happen when they're back.

>> congratulations for your year of service. >> over 49 weeks, scott kelly and his russian comrade have taken more than 5400 spins around the earth, taken part in six space walks and carried out experiments including growing edible vegetables in zero gravity conditions, but it's how their own bodies have weathered the long spell of radiation exposure and weightlessness that researchers will be giving the most attention. kelly said he feels fine physically but has a keener sense of the social isolation of space travel. after spending almost half the time in a box the size of a phone booth, kelly points to the designing a human journey to human journey to mars that could take 500 days or more. >> making that, you know, that private area as perfect as possible, i think will go a long way towards reducing fatigue, reducing stress. >> while scientists will collect data from the two astronauts, the american will be subject to

closer examination together with his twin brother, mark. >> i've provide samples, blood, saliva, other things i am not going to go into, and be there for m.r.i.'s and ultrasounds. >> they will be compared for changes to their vision, the interactive system of bacteria within each human body, the chromosomes that determine aging and to their immune systems after both receive the same flu vaccine. >> we are using our latest technology for gene sequencing to really identify each t. cells in mark and scott and try to see how they react to the flu. >> kelly said he could have spent another year on the space station if necessary, but back on the ground, will continue to be a focus of close study to

researchers charting the next years of humankind and frontiers in space. thanks for watching. the news continues next. >> announcer: this is al jazeera. ♪ hello and welcome to the news hour. i'm martine dennis. this is al jazeera live from doha. coming up in the next 60 minutes. voting gets underway in one of the most important days in the u.s. election. 130,000 in just two months. refugees keep arriving in europe, and the continent is divided on what to do with them. ♪ spy