Transcript for 'Teflon Trump' Popularity Climbing After Republican Debate
Now, to new developments in the race for 2016. The fallout after fight night for the republicans. Donald Trump, center stage, but the real duel was between two others on that stage, who are hoping to break through, should trump falter. Tonight, we take you into the massive crowd in Arizona, welcoming trump after the debate. ABC's Cecilia Vega is in Mesa tonight. Reporter: Donald Trump today, pulling his private plane right into his Arizona rally, to what else? The theme song from the movie "Air force one." Please welcome the next president of the United States, Donald J. Trump! Reporter: Trump is riding high. He's calling last night's debate his best yet. And these supporters agree. There are thousands of people inside this hangar just to catch a glimpse of Donald Trump. We have the biggest crowds by far. Because there's a movement going on, folks. This isn't just, let's go and have a good time. Somebody said, "Oh, trump is a great entertainer." That's a lot of . Reporter: Trump then hopping back on his plane, bound for Hollywood. In the final republican debate of 2015, teflon trump fighting off his rivals, namely Jeb bush. This is a tough business, to run for president. You're a tough guy, Jeb. I know. We need to have a leader that's -- You're tough. You're never going to be president of the United States by insulting your way to the presidency. I'm at 42 and you're at 3. So far, I'm doing better. Doesn't matter. Doesn't matter. So far, I'm doing better. You started off over here and moving over further and further. Pretty soon you're going to be off the end. Reporter: But the most anticipated battle of all never happened. Ted Cruz, now surging in the polls, and despite just days earlier, trump accusing Cruz of being a maniac in the senate. Last night, he played nice. He has a wonderful temperament. He's just fine. Don't worry about it. Okay. Reporter: Cruz not laying a finger on trump, either, saving his fire for Marco Rubio. The two senators vying to be the republican alternative to the brash billionaire, sparring on immigration. Some chose, like senator Rubio, to stand with Barack Obama and chuck Schumer and support a massive amnesty plan. Reporter: But Rubio fired back, questioning Cruz's own position on amnesty. Does Ted Cruz rule out ever legalizing people that are in this country illegally now? Nor senator Cruz? I have never -- Do you rule it out? I have never supported legalization and I do not intend to support legalization. And Cecilia Vega with us live tonight from Arizona. You were in that hall last night. Donald Trump with another promise, that he will not run as an independent? Reporter: Yeah, that's right, David. Republicans were worried that a third party run would split the vote and hand the white house to the democrats in 2016. But last night, trump promising unequivocally to run as a republican. He says that he is, now, quote, totally committed to the republican party. David? Cecilia Vega live in Arizona. Cecilia, thank you. ABC's chief white house correspondent Jonathan Karl is in Washington tonight, and Jon, many saying trump did nothing last night to damage his lead in the polls. But not just many rrm voters that want trump, the Clinton campaign might want him, too. You are well aware of this. All the leading republicans standing on that stage, the newest polling shows she has the best shot against trump tonight. Reporter: In fact, in virtually every public poll since Donald Trump got into this race, Hillary Clinton does better against trump than any other republican. And her lead over trump is actually expanding, even as trump has solidified his support among republicans. But I have to tell you, trump supporters just aren't buying it. Our poll this week, the overwhelming majority of republican voters said they believe Donald Trump has the best chance of winning in November. All right, a really interesting dynamic there. Jon Karl live at the white house front. Jon, thank you. Of course, the democrats
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