Transcript for Republicans Prepare to Debate Ahead of New Hampshire Primary
The big game in American politic, the final republican debate before the New Hampshire primary. It's going to take place in this hall here in Manchester, new Hampshire and air live right here on ABC. And the stakes couldn't be higher. It's crunch time. Every candidate on the stage all seven of them need to make a mark. We have team coverage this morning starting with ABC's Tom llamas live from the debate hall. Reporter: Good morning to you, Paula. Two big battles happening tonight. The first center stage, Donald Trump and senators Marco Rubio and Ted Cruz fighting to take over this race and then there's everyone else left in the field, hoping to have a moment that resonates with New Hampshire voters and there will be men on that stage tonight fighting for their political lives. This morning, Donald Trump is heading to New Hampshire and staying there till the voting is over on Tuesday. You have the most beautiful churches I've seen. I mean, these churches. Seriously. Reporter: But overnight a quick stop in South Carolina. I almost want to just go in and pray. Reporter: Trump hopes his last-minute New Hampshire blitz will deliver a better result than Iowa. His team of volunteers going door to door. We just wanted to send out a reminder, hand you a reminder and see if we can get your support for trump on Tuesday. Reporter: We're with them trudging through the snow. Is it worth it. It's Victoria's secret worth it. We have to take back our country and not let it be in the wreck that it's in. Reporter: Another ground army, as well. Good morning. They're showing the type of dedication that helped Cruz win in Iowa. 'S and a walking around here probably not going to change a lot of hearts and minds individually. Reporter: You never know. If it's one vote it's worth it. Reporter: Senator Cruz hoping to extend his winning streak talking up an issue critical to New Hampshire voters. The reason the second amendment is in the bill of rights, each and every one of us has a god-given right to defend our home, family and our children. Reporter: But Cruz is feeling the pressure. Rubio surging in the polls, the target on his back getting bigger. His record of accomplishment is slim. He's willing to break his word to the voters and make deals with democrats. We know who the boy in the bumble is up here. Reporter: Rubio feels the attacks are growing because his campaign is taking off. Get a call on Tuesday night saying I dropped out, it isn't true. It's a lie, keep voting. Reporter: Now, Rubio, of course, referring to the Cruz campaign's effort on caucus day in Iowa suggesting that Dr. Ben Carson was dropping out of the race. That, of course, never happened and Cruz later apologized to Dr. Carson. Rubio's gone into this debate feeling that everyone will be out there to attack him. He did get a boost overnight, former rival and Louisiana governor bobby jindal endorsing him. A little boost there. Tom covering this campaign every step of the way, Tom, thank you. Let's get pregame analysis with Matthew dowd also right there in the debate hall. Hey, Matt, good morning. I guess my first question is how high are the stakes generally tonight? I mean, I think tonight is the most important event in the republican race up until this time. It sets everything up for super -- I mean for Tuesday in New Hampshire and this moment with all seven on stage, each of them has a huge stake in what's going to happen tonight. What the individual candidates need to do tonight. Trump is leading in the polls but others have been gaining on him so how does he maintain poll position? Reporter: I think Donald Trump, he needs to make sure he's about ten points up right now. He needs to make sure he stays there and I think one of the ways to do that, be strong but he actually needs to deliver a very calm and steady way, not in the manner he's done in previous debates but straightforward but exceedingly calm and cool. Exceedingly calm and cool. We'll see if he can go there. Marco Rubio got the best bounce out of Iowa. He's now in second place in the polls. What do you think his strategy is going to be tonight in the face of the inevitable attacks from his rivals? Reporter: Well, you know, it's interesting, Marco Rubio finished third in Iowa but he stepped all over Ted Cruz who finished first in Iowa and Ted Cruz hasn't gotten any lift out of Iowa. I think Marco Rubio will be under assault by everybody on that stage especially the governors or former governors trying to figure out a way to move on from here. I think what you'll see tonight is basically everybody knows that there's only four tickets out of New Hampshire so of those seven on stage only four are going to be able to get out of here once Tuesday voting starts. As you said stakes incredibly high, Matthew dowd, we appreciate your analysis on Saturday morning. Then there would be four. As we head into tonight's debate we're getting a glimpse in the candidates' pregame rituals courtesy of the website the independent journal review. My favorite thing to do on the day of the debate is play plants versus zombies on my iPhone with my two girls. Siri, what questions will David Muir be asking. I normally call my mom to get advice. Interesting. I didn't know there was a zombie game he was playing. That's an odd way to prepare. Download that now, Dan. I'm all over it, David Muir and Martha Raddatz will be moderating tonight's debate. They've got a preview now from the debate hall. Hey, Dan and Paula, good morning. We're hours away from the seven gop candidates taking the stage right here behind Martha & me in Manchester, New Hampshire. And Donald Trump will be at the center because he is the front-runner based on polling, Cruz and Rubio will be on either side of him and that's the top three. But there's going to be a lot of focus on the other four, Carson, kasich, Christie and bush looking to survive the race so they'll make their case certainly to voters right here in New Hampshire to try to change the course of the race. Anything can happen so join me and David only on ABC here live in New Hampshire, we'll be asking the questions and it all starts at 8 P.M., 7 central. We have to get back to work. See you tonight.
This transcript has been automatically generated and may not be 100% accurate.