The following is a partial transcript of the Dec. 30, 2007, edition of "FOX News Sunday With Chris Wallace":

"FOX NEWS SUNDAY" HOST CHRIS WALLACE: Joining us now, the authority on the Iowa caucuses, David Yepsen, political columnist for the Des Moines Register.

And, David, welcome back to "FOX News Sunday."

DES MOINES REGISTER POLITICAL COLUMNIST DAVID YEPSEN: Good to be with you.

WALLACE: Let's get right to it and start with the Democrats. How do you see the race four days from right now?

YEPSEN: Dead heat. All these polls show this thing is a statistical tie, and so it's a dead heat. No predictions.

WALLACE: There's been some talk that the Obama surge has flattened a bit and that Edwards has the late momentum. Do you see signs of either of that?

YEPSEN: Yeah, I think that there may be something to that. There are two wild cards in this — in the Democratic contest. One is can Hillary Clinton attract new women, older women, to the caucuses. And the second one is can Barack Obama attract a lot of young people.

They both need to add people to the electorate, because John Edwards has got such a strong base of support with a lot of party regulars. So those are the two wild cards, older women and younger voters.

WALLACE: Well, you talk about the fact that Edwards may have some late momentum. He's been there for — it seems like he's been living there since 2005. Why would there be now a late movement towards him?

YEPSEN: Well, because Democrats like all of these candidates, Chris. You know, on the Democratic side, the party activists are having trouble deciding among six candidates they really like.

And so for a lot of people, it's a matter of coming back home to John Edwards; whereas on the Republican side, there's been a lot of concern. There isn't as much enthusiasm for some of their candidates as there is on the Democratic side.

WALLACE: Who is it, do you think, on the Democratic side has the best field organization? And you mentioned the fact that Obama is trying to do something that hasn't been done, to get younger voters.

He's particularly talking even about college students coming back early from vacation. Any sign that that's actually going to work?

YEPSEN: Well, his people will tell you that they're not predicating their whole campaign on young people. They see that as primarily a lot of gravy that they'd like to add.

But it is something that they've tried to do, is to get students to either — particularly to go home and caucus rather than caucus in their college towns.

If you're an Iowa student, it's going to leverage Barack Obama more votes, more delegates, to have them caucus at home. But these younger voters just historically have not been big caucus-goers.

There are some signs that that's changing, both in Barack Obama's case and I think in Ron Paul's case on the Republican side.

WALLACE: And of the three, as it stands right now, who's got the best field organization?

YEPSEN: You know, you can't answer that, Chris. They are all really excellent organizations. I might give a little bit of an edge to Hillary Clinton on that, but, boy, not by much.

WALLACE: After the Bhutto assassination, the three Democratic frontrunners and, in fact, all of the Republicans were scrambling to establish their foreign policy credentials.

Any sense at all that the events in Pakistan have changed this election and made it more about national security?

YEPSEN: Yes, I think so. I think it causes voters a little pause. I don't think it causes them to switch from one candidate to another. But caucus-goers — we've had a lot of talk about how undecided they are.

These are sophisticated voters, activists in both parties. They pay attention to public affairs. This is the kind of late development that makes them say, "Hmm, let's take another look here. Let's wait a little bit longer."

I think it helps those candidates who have some portfolio on foreign policy issues, and I think it hurts those who have candidacies that are based more on domestic questions.

I think the situation with Governor Huckabee is a good example that you were talking about with Senator Thompson. Some of these later polls have shown Mike Huckabee to be dropping a little bit and Mitt Romney to be picking back up.

And the reason for that, I think, is people are saying, "Well, maybe Mike Huckabee doesn't have what it takes on national security questions." So I think it does have that effect.

We saw it four years ago, Chris, with Howard Dean sort of fumbling the capture of Saddam Hussein with something that hurt his candidacy at the end.

WALLACE: I'm going to get to the Republicans in a second. And I know you said right at the start it's too close for a prediction.

But having said that, and I know that you say that there's a deck full of wild cards here, but four days out, if I really pressed you, who do you think would win on the Democratic side?

YEPSEN: Now, Chris, four years ago, you got me to predict Howard Dean, and I'm still wiping the egg off my face. You should ask Bill Kristol that, because he's the only guy that picked John Kerry, as I recall, so I can't predict this time.

WALLACE: Well, you know, he's still dining out on that, and we'll talk to him later on. So all right. I'll take that as a definite maybe.

Let's turn to the Republicans. How do you see that race right now?

YEPSEN: Well, Mike Huckabee surged here lately, and it was quite a phenomenon. He captured the support of a lot of social conservatives. He captured a lot — the home schoolers, the fair tax people, the national sales tax people. And he really rocketed in a nice fashion.

In the last few days, though, I think it's tightened up some. Mitt Romney clearly has the best organization. Mike Huckabee has sort of had to borrow his organization from social and religious conservatives.

So right now I think it's an — it's whether to see if Mitt Romney can stage a comeback here in the last few days.

WALLACE: Do you think that — you know, we've been making a big deal about misstatements by Huckabee in a variety of areas in the immediate aftermath, and one of them — you pointed out that he said my apologies, when he meant sympathies, to the Pakistani people.

Do you think the Iowa voters are paying attention to that and that it's concerning them?

YEPSEN: Yes. I think Republican caucus-goers, like Democratic caucus-goers — they're looking for a candidate who they think can win. They want somebody they like. And clearly, Mike Huckabee is a very endearing and likable person.

They want somebody who they see as president. And they want somebody who they see as a good candidate. Electability is a big issue with a lot of these activists.

And when something like that happens, particularly so close to the end, with all this indecision, it does make some — I think it makes some Republican caucus-goers pause for a moment and say, "Well, maybe Mike Huckabee isn't what we want to go with. Maybe we want to look at a Fred Thompson or some other candidate."

WALLACE: Now, Romney is the only one who's running negative ads in Iowa. And there is a conventional wisdom which — I'm going to ask you how founded in truth it is — that going negative is poison in Iowa.

One, is it? And two, does that mean that those negative ads by Romney are backfiring?

YEPSEN: Well, people say that it's poison, and there is a lot of support for a civil campaign. But the fact of the matter is negative political commercials do work. They do make a contrast.

And Governor Huckabee has been pounded by attack ads, not just from Mitt Romney, but from these 527s, from these independent expenditure groups, from Club for Growth. And I think that has taken a toll on him in the last few days.

WALLACE: So you ducked the prediction on the Democratic side. On the Republican side, you want to pick between Romney and Huckabee?

YEPSEN: No, I'm going to duck that one, too, Chris, because, again, it is — some of these polls now at the very end show this within the margin of error. So it's pure gambling to predict.

WALLACE: Now, there's also finishing third in Iowa, and it apparently is going to be something of a margin between the top two. And it seems like it's coming down to McCain and Thompson. Is McCain making a late surge in Iowa?

YEPSEN: Yes, I think he is. And I think these national security questions are playing a part in that. Some of the immigration debate has faded somewhat. It's still an important issue in the Republican party, but it's not quite edge of the news.

The conflict in Iraq is going better for the United States, which sort of vindicates some of John McCain's earlier positions. So I think he has enjoyed a bit of an uptick here.

And there really is a competition for third place out of here. Historically, as we all know, there's three tickets out of Iowa. And so you've got Fred Thompson and John McCain, and Rudy Giuliani is back.

And I also think that Ron Paul is a wild card in this third-place position. If he brings a lot of new people out to the electorate and there's a lot of energy there, then I think he could be competitive for that as well.

WALLACE: And explain that. I mean, if you've got Romney and Huckabee, and they're 10 or 15 points ahead of whoever finishes third, why does it matter who's third?

YEPSEN: Well, it matters who's third in terms of the ability to stay in the race. Historically, anybody who finishes worse than third simply runs out of momentum.

They can't raise money. They have no energy going on to these later contests. And with these contests packed so closely together, they have no opportunity to recover.

So third place, as I always say, is the standby ticket out of Iowa to New Hampshire. It's no guarantee of anything.

WALLACE: We've got less than a minute left. You know, the big unknown in this, because we're really in uncharted water, David, is the fact that the race has gotten so tight. And where it used to be a week or two weeks to New Hampshire, it's only going to be five days.

Do you think that makes the winner in Iowa more or less important?

YEPSEN: I think it makes it more important. You know, the law of unintended consequences is at work here. All these other states that don't like Iowa and New Hampshire have moved their contests up closer to the state of Iowa and to New Hampshire.

Now, if a candidate stumbles, they've got no — little time to recover. And if they do well, they could light their rocket and ride it all the way to the nomination, which is what John Kerry did four years ago. So winning Iowa is particularly important.

It's particularly important on the Democratic side. Hillary Clinton wins this — she could reignite her campaign. If she loses, she stumbles, then I think Barack Obama is in a position to run the table. And certainly, John Edwards lives to fight again another day in another state.

WALLACE: David, we're going to have to leave it there, but we'll see you in a couple of days in Des Moines. And thank you so much for talking with us.

YEPSEN: Thank you, Chris.