Transcript for The 1st GOP Presidential Debate: Who's in, Who's Out
Now to that first big showdown in the race for the white house. The field set for tomorrow night's republican debate. Ten candidates made the final count led a front-runner Donald Trump. He'll join us in a moment first setting the stage with Jon Karl. This is the most highly anticipated primary debate we have ever seen at this point in the process and that is almost entirely because of the unpredictable billionaire candidate who will be standing at center stage. The stage is set. Fox News announcing the top ten gop candidates scheduled to face off tomorrow night. Taking center stage, the clear front-runner, Donald Trump. Flanked by Scott walker and Jeb bush, the only other candidates polling in double digits. Even bush is now calling trump the man to beat. While still criticizing his tone. I respect a guy who's the front-runner in the republican nomination but I think to win and to govern the right way we have to unite rather than divide. Reporter: Joining them on center stage, Marco Rubio, Ben Carson, Mike Huckabee, Ted Cruz and Rand Paul, the lower their ranking the farther they are from center stage. New Jersey governor Chris Christie polling at the bottom at just over % placed at the far edge of the stage along with Ohio governor John kasich. Trump's position at the center of Thursday's showdown would have been impossible to forecast when he announced his run just seven weeks ago. And many predicted trump's support would plummet after his controversial comments last month on John McCain. He's a war hero because he was captured. I like people that weren't captured, okay. Reporter: But the trump train keeps on rolling. One critical factor, 79% of republicans say that trump says what he believes, not just what he wants people to hear. And one thing we have seen so far is that attacking Donald Trump just doesn't seem to work. In fact, the two candidates who have gone at trump the hardest, Rick Perry and Lindsey graham are so far down in the poll, George, they won't even be on the debate stage tomorrow night. Thank you, Jon.
This transcript has been automatically generated and may not be 100% accurate.