John Edwards -- I don't actually know what he's going to do, because he's got a choice to make tonight. He's got to decide who his opponent is in New Hampshire. Is it Hillary Clinton or Barack Obama? Out on the stump in the last few days, he's been kind of ignoring Senator Clinton and focusing more on Obama. We'll see what he does tonight.
And finally, Bill Richardson is going to be in there. And he might have to change tonight as well. All through these debates, he has been very nice to Senator Clinton. He's been the one backing her up and saying, "Everybody should be positive."
But I've got to tell you, right now, the Clinton campaign and the Clintons themselves are livid at Governor Bill Richardson, because they believe he made these deals with Barack Obama in the Iowa caucuses to throw his support in the places where he wasn't viable to Barack Obama so he could stay in the race.
STEPHANOPOULOS: And it will be interesting to see the body language and the play between Richardson and Clinton tonight because of that.
SAWYER: Well, let's talk about a couple of the things Senator Clinton did on the campaign trail just today -- changed a few of her tactics.
She took questions at great length. Even for a couple of hours, she took questions.
She had some independent young voters traveling along with her.
STEPHANOPOULOS: I think they're responding to what happened on Thursday night, the tableaux of Bill Clinton and Madeleine Albright, not looking like change.
Also, she's taking a page out of her husband's playbook from 1992. Campaign round the clock; answer every question.
John McCain did it, too, in 2000. It works in New Hampshire.
SAWYER: All right.
Here it goes, once again. Another high-stakes moment. It is the Democrats turn. And Charlie Gibson is in Manchester, New Hampshire.
GIBSON: Thank you very much, Diana.
And thank you, George.
We are back at the Dana Humanities Center at Saint Anselm College here in Manchester, New Hampshire.
And I am delighted to say that the four leading Democratic presidential candidates vying for the Democratic nomination are all joining us this evening. And we have, again, drawn lots for their placement on the stage.
GIBSON: And so let me introduce them from left to right. We have with us former Senator John Edwards of North Carolina, Senator Barack Obama of Illinois, Governor Bill Richardson of New Mexico and Senator Hillary Clinton from New York.
And again, for the first 45 minutes of this debate, I will be posing questions in three rather broad categories. We'll do 15 minutes each, but with the hope that I can sort of stay out of the way to the extent possible and let the candidates discuss the issues among themselves.
There are no lights to limit -- time limits, at least for this part of the debate. But I will interrupt politely, I hope, if things seem to be going a little bit long.
GIBSON: So let me start with what is generally agreed to be, I think, the greatest threat to the United States today, and, somewhat to my surprise, has not been discussed as much in the presidential debates this year as I thought would be, and that is nuclear terrorism.
And for some background, here's ABC's Chief Investigative Correspondent Brian Ross.
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