'This Week' Transcript: GOP Candidate Rick Santorum

WASHINGTON, March 18, 2012— -- KARL: Good morning. And welcome to This Week.

(BEGIN VIDEOTAPE)

KARL: It's a two-man race.

SANTORUM: We did it again.

KARL: Santorum sweeps the South. Can he take the fight to the convention?

SANTORUM: The time is now for conservatives to pull together.

KARL: Can Mitt Romney regain his momentum?

ROMNEY: Senator Santorum is at the desperate end of his campaign.

KARL: And how will Republicans reunite after this bruising contest? Questions this morning for our headliner, the man who continues to surprise, Rick Santorum.

Then, the White House on offense.

BIDEN: Mitt Romney, Rick Santorum and Newt Gingrich, these guys have a fundamentally different economic philosophy than we do.

KARL: And on defense, after a tragedy in Afghanistan.

OBAMA: No one wants it. This is a hard slog. This is hard work.

KARL: That and the rest of this week's politics with our powerhouse roundtable. George Will, Haley Barbour, Bill Burton, Nia-Malika Henderson and David Ignatius.

Good morning, everyone. George Stephanopoulos has a well-deserved morning off.

It's been a wild week on the campaign trail with voters in Alabama and Mississippi giving Rick Santorum's campaign a lifeline. Yet in the all-important delegate race, Mitt Romney still holds a big lead. With 496 delegates, Romney has nearly twice as many as Santorum, and he is almost halfway to the magic number; 1,144 needed to win the nomination.

But our headliner this morning has been on a roll. Former Senator Rick Santorum joins us now. Good morning, Senator.

SANTORUM: Good morning, Jonathan. Good to be with you.

KARL: So, Senator, front page of the New York Times today has a big headline saying Republicans are girding for a fight on the convention floor. You have been saying this for days, saying that basically nobody can really get a majority of the delegates before the convention. Are you saying essentially that your best chance of winning this nomination is a fight on the convention floor?

SANTORUM: Well, we still believe that there are plenty of delegates out there for us to do what we have been doing, which is actually going out there and winning states and winning the tough battles, and doing so over pretty overwhelming odds. If you consider the fact that we're, you know, to deal with Congressman Gingrich, Speaker Gingrich, who is in this race and certainly pulling more votes from us than he is from Governor Romney, and being outspent. You know, here in Illinois, when I was just there yesterday, you know, by 10 to 1, yet we're hanging in there, we're fighting, we're climbing, because we have got the best message, the best contrast with President Obama and the best vision for our country. And I think that's what people are responding to, and I think they're getting tired of the negative ads. They're getting tired of just tearing down the other side, which is what Romney has been doing now for two elections in a row, and really providing no real vision for the country.

KARL: But how likely do you think it is that this is going to come to a battle on the convention floor? As you know, this is something that Romney has said would doom the party's chances against Barack Obama?