another huge story, the once-inevitable hillary clinton locked in a dead heat with a surging bernie sanders. behind the scenes with the campaigns as it came down to the wire. candidates practically begging people to caucus. >> get out of bed and caucus! >> hind each candidate an army of volunteers. also the running mates. we're with the men and women who know the candidates better than anybody. a rare insight into love and politics. >> he will be unbelievable. >> tonight what the candidates' spouses are telling us about stumping right by their side. first tonight the "nightline 5". >> the bold nissan rogue with intuitive all-wheel drive. because winter needs a hero.

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seconds. good evening. in a presidential race that has been wild and unpredictable, tonight the voters weighed in for the first time and they made things even more wild and unpredictable. here now the numbers out of the iowa caucuses. on the republican side, a big projected victory tonight for texas senator ted cruz. he comes out on top. this is a surprise. followed by the billionaire businessman and ex-reality star donald trump who had been leading in the polls coming into tonight. a close third, and this is another surprise, florida senator marco rubio finishing much stronger than expected. meanwhile, let's talk about the democrats.

clinton neck and neck right now with vermont senator bernie sanders. originally written off as a fringe candidate. that race still too close to call. we have team coverage on this momentous evening and we start with abc's jon karl who's at cruz headquarters, good evening. >> reporter: trooults is the first republican to get into a brawl with donald trump. and to beat him. this was a triumph of organization. he did it with a single-minded focus on iowa and the evangelical voters that dominate here. as for donald trump, he has a new title tonight -- loser. after dominating the polls for months, he has now lost the first contest. in fact, marco rubio had such a strong showing here, 23%, that he almost beat trump out for second place. let me tell you, this is just the beginning. donald trump is now on his way to new hampshire, a state where he has a huge lead. far bigger than he ever had in iowa. so stay tuned.

>> a long road for both the republicans and the democrats. jon karl, thank you. so much to talk about tonight. so let's bring in abc news political analyst matthew dowd, good evening, sir. so we've seen in the past conservative candidates win in iowa and then go on to fit zell. so does ted cruz have a clear path to the nomination at this point? >> no, he doesn't have a clear path to the nomination. iowa's caucus has a larger percentage of evangelical voters than a other state he's going to be faced with in the rest of the process. he doesn't have a state now where he can put together the same coalition. he's going to figure out where he can win next and do the same thing in iowa. >> another big story tonight, donald trump, he's been the big story of this campaign. let's listen to a little bit of his concession speech. here it is. >> in fact, i think i might come here and buy a farm. i love it, okay? thank you. thank you, everybody. >> so three words that you don't often hear associated with donald trump.

how big a defeat is this for him? >> he had an opportunity, if he had won tonight, as the leader, to start putting this race away and running the table. he would have won new hampshire, won south carolina, begun to put the race away. he no longer can do that, it's a three-perpendicular race. now it's incumbent upon him, it's a must to win new hampshire next week. >> it as wide-open race. >> completely, completely. >> rubio surging tonight as well. before i let you go i want to talk about the democrats. we have hillary clinton who was once considered inevitable, a shoo-in. almost beaten by a 74-year-old former socialist. how much trouble is she this? >> she like donald trump, she had an opportunity to basically start to put this race away with a clear victory tonight. she didn't get that. now she faces a likely loss in new hampshire. so the next place she can win is south carolina. so that race is now -- which could have been shortened if she had won tonight overwhelmingly -- is going to be a much longer race and go into march for sure.

so many amazing moments tonight. for a look at the sights and sounds from a historic evening, abc's david wright at the sanders headquarters. good evening to you. >> reporter: good evening. the sanders crowd highly energized here tonight. on one side of this race you've got a cliff hanger. on the other side an upset. true to form, 2016 seems to be shaping up to be a year where the pundits might as well hang up their hats and hang on for the ride. >> god bless the great state of iowa. >> reporter: tonight more signs that nothing is inevitable in 2016. on the republican side, ted cruz trumped billion fair donald trump. >> iowa has sent notice that the republican nominee and the next president of the united states will not be chosen by the media. will not be chosen by the washington establishment.

people, the american people. >> reporter: on the democratic side, too close to project. even as hillary clinton seemed to declare victory -- >> so as i stand here tonight, breathing a big sigh of relief, thank you iowa! i want you to know i will keep doing what i have done my entire life. >> reporter: bernie sanders isn't conceding anything. >> it looks like we are in a virtual tie. >> reporter: the hard-fought campaign touched every corner of this rural farm state. all 99 counties. >> the eyes of the world are watching us tonight. >> reporter: a record number of gop caucusgoers turned out to participate, more than 180,000 statewide. for donald trump, the front-runner most of the way here, the question has always

the trump rallies translate into huge crowds of trump voters? >> get out of bed and caucus. you got to do it. >> reporter: tonight he was still talking that way. even in second place donald trump still tried to sound like a winner. >> we finished second and i want to tell you something. i'm just honored. i'm really honored. and i want to congratulate ted. >> reporter: trump may well have been hurt by this line -- >> how stupid are the people of iowa? >> reporter: which came back to haunt him in cruz's campaign ads. >> how stupid are the people of iowa? >> reporter: also, it may not have helped that he skipped that last debate. the third place finisher on the republican side, marco rubio, also treated tonight as victory. >> for months they told us we had no chance. >> reporter: now a caucus gets a lot of attention because it comes first. but in many ways this state is not exactly representative of the rest of the nation. eight years ago mike huckabee won here.

>> more than 90% white, you look at it from a religious standpoint more evangelicals per captain than the rest of the country. but it's also the state that gave the green light to president obama. >> reporter: the ad war brutal, up to the wire. the big day is here in a few hours we should know the winners of the iowa caucuses -- >> reporter: the evening news tonight -- >> postal workers to nurses, he's been endorsed for real change. bernie sanders. >> reporter: including a mini campaign debate in every commercial break. >> in a world as complex as this, we need a president as experienced as hillary. >> reporter: it's been like this for months. the campaigns and their super pacs spent more than $70 million on ads here. >> i'm rand paul. >> i'm john kasich. >> i'm chris christie i approve this message. >> reporter: 17,000 ads airing in this state during the last month alone. that's the equivalent of six full days of political ads 24/7. >> hi, iowa, i'm ivanka trump. >> reporter: donald trump's

and tell ad. the glamorous new york socialite explaining to iowa voters how the caucus system works. >> i am really excited to tell you how to caucus for my father, donald j. trump. >> reporter: a lot of them first-time caucusgoers. people like 17-year-old maggie norland and her mom lauren attending their first caucus. both of them slightly undecided. >> you're coming in with an open mind? >> yeah, definitely. >> somewhat, somewhat. >> somewhat? you have an idea of who you want to vote for? >> yeah. >> but you're ready to be persuaded if somebody else can persuade you? >> exactly. >> reporter: they were leaning towards martin o'mally but well aware he might not meet the threshold to survive. we asked the vice principal of the school where the caucus is being held to explain the process. what advice would you have for them in how to approach this whole thing? >> would i would do is know this is a very fluid process. >> we're going to start the count -- >> in theory the hillary people on one side, the bernie people

going to be trying to get the o'mally people to come to them? >> exactly. all of a sudden the o'mally people will have more significance in this process. >> reporter: tonight o'mally suspended his campaign, freeing his voters to move to one or the other democratic candidates. >> we fought very, very hard in order to give the people a choice. and the people have made their choice tonight. >> reporter: the iowa caucus is always a test of organization, not just inspiration. today an army of volunteers helped out. we met this 13-year-old girl phone banki for ted cruz. >> i made 833 calls for ted cruz. >> reporter: and there was jim kay at sanders headquarters. >> have you ever done this before? >> no. >> where did you come from? >> phoenix. >> you drove from phoenix? >> starting yesterday morning. >> to be here to help with the caucus? >> yes. >> how come? >> iowa is really a place where i feel like i can make a difference sgln. >> reporter: tonight he made a

calls at sanders headquarters, directing vote toes their caucus sites. >> what can i help you out with? sure, i can get you your caucus location. >> reporter: he's 30 years old, an electrical engineer who took time off work to be here. that's how strongly he feels. no sooner have the caucus results been counted and it's onward to new hampshire. some with a boost, others slightly bruised. the battle in both parties now in full swing. >> on to new hampshire. so long, everybody. >> reporter: i'm david wright for "nightline" in des moines. next we go up close with the people who see a side of the presidential candidates most of us will never glimpse. their spouses. how does marriage survive on the campaign trail? type 2 diabetes doesn't care who you are. man woman or where you're from. city country we're just everyday people fighting high blood sugar. i am everyday people.

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marriage can be tricky under any circumstances. but imagine what it's like in the crucible of a presidential campaign. tonight abc's linsey davis spends time with the people who know the candidates better than anybody, their spouses. >> reporter: tonight in iowa, the candidates in a hard-fought race. at their sides, their real-life running mates, one of whom could end up becoming the next first spouse. >> give it up for michelle obama! >> reporter: it was eight years ago that many voters met a young michelle obama for the first time, standing next to her husband as he won the iowa caucus in 2008. as the old adage goes, you can tell a lot about a person by the company he or she keeps. >> look at her. >> reporter: which is why abc news recently sat down with some

first lady, or the first first gentleman. >> i've been married 29 years. >> 18 years. >> 25 years. >> and the next president of the united states -- >> is my running mate. >> my running mate. >> bernie sanders. >> dr. ben carson. >> ted cruz. >> i'm here to tell you, collectively they play the a mean game of pool. cooked up some meatballs. >> simmer them in a sauce all day long -- >> reporter: went out running on the street and out on the trail. took me bird watching, introduced me to their grandchildren -- >> done! >> reporter: and sometimes even let down their hair. >> i've never told anybody that. >> what made you fall in love with chris? >> he had great stories. he still has great stories. and he was cute. >> reporter: tonight all eyes on the front runners, all with very different love stories. for the cruzs it was a love story that blossomed out of politics. as they worked on george w. bush's campaign in 2000. >> i've always been certain about ted's talent.

people could see what i saw, that people would vote for him. >> you've said it was love at first sight? >> i found ted very compelling. he is a warm person, he's friendly, he's smart, he also likes to have fun. >> thank you for being here, that is a huge contribution to this election. >> reporter: heidi, harvard business school grad, put her position as a goldman sachs executive on hold to hit the trail with her husband. do you think working at goldman is at all a political liability for your husband running for president? >> you know, i've been asked if ted is anti-wall street. and ted is not anti-wall street, he's not anti any business. he is against government subsidies for any industries. and he's said that over and over. >> people seem to either love or hate ted cruz. why do you think he's so polarizing? >> he's happy to expose the inequities. he's happy to tell the truth. if you're not on the side of the truth, if you are not in there

don't like the problem fixer. >> when we met, it will soon be 45 years ago in a couple of months, when we met, we fell in love. >> reporter: former president bill clinton has hit the trail for his wife, telling the tale of their courtship which began at the yale law school library. >> she closed her law book, walked the entire length of the library, walked to me, she said, look. if you're going to keep staring at me, and i'm going to keep staring back, we at least ought to know each other's name. i'm hillary rodham, what's your name? >> reporter: after multiple proposals she finally said yes. the two were married in their living room with 15 gists. a tad less extravagant than the wedding of donald trump that the clintons attended in 2005. >> he will be unbelievable, the best dealmaker, the best master negotiator. >> reporter: melana trump has

sat down with abc's barbara walters. >> how do you feel about campaigning? >> well, it's my choice not to be there. i support my husband 100%. but we have a 9-year-old son together, baron, and i'm raising him. >> reporter: jane sanders touts her husband as a problem solver, something she says first attracted her to him when he ran for mayor of burlington, vermont. >> when he was running for mayor he knocked on every door. and i opened the inside door and i said, don't worry, you've got my vote. and that was it, the first words i spoke to bernie. >> reporter: while her husband of 27 years now tries to woo america, she finally recounts her own courtship and the very first date. >> i was outside talking to some friends. and he came out and said hello. then kept on walking. he turned back again. and said, have you eaten? and of course i had but i said, no. so we went out to eat.

so this is the wedding. and my daughters were my brides maids. and davey walked me down the aisle. >> reporter: they're inseparable in this campaign, they have his and hers desks. >> we work together. so he's -- also, he's gone a lot. so -- you know, since having a separate office from me. >> reporter: florida senator marco rubio ostensibly has the biggest cheerleader of all in his running mate and wife of 17 years, janette rubio. >> hi, how are you? >> reporter: a former actual cheerleader for the miami dolphins. they are high school sweethearts who met just down the road from their home today. shortly after announcing his candidacy for president, the parents of four sat down with george stephanopoulos. >> tell us, was he smooth? is that a no? >> well -- >> i was funny. >> he was funny. that he was. he was funny. he definitely charmed me with his humor.

for all of these spouses who know only one candidate will end up taking the oath of office. but each of them has already made a vow, to love and to cherish forever. for "nightline" i'm linsey davis in new york. >> oval office or not. and to watch the full episodes of our naibs news digital series "running mates" head to abcnews.com. we'll be right back. [screaming] the bold nissan rogue,with intuitive all wheel drive. because winter needs a hero. now get a $199 per month lease on the 2016 nissan rogue. nissan. innovation that excites. e trade is all about seizing opportunity.

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finally tonight, a recap of our top story. a huge and surprising night in the iowa caucuses. on the republican side the

ted cruz, who edged out the billionaire businessman donald polls. another surprise, florida senator marco rubio coming in a close third, beating expectations. on the democratic side it is too close to project. hillary clinton, once considered the formidable front-runner, locked in a dead heat with vermont senator bernie sanders. thank you for watching "nightline" tonight. marco rubio will be live on gma first thing in the morning. as always we are online 24/7 on our "nightline" facebook page and at abcnews.com.