PERRY: It was true then. It is true now.
ROMNEY: Rick? $10,000 bet.
PERRY: I'm not in a betting business.
ROMNEY: Oh, OK.
KARL: Romney probably would have won that bet. But who bets $10,000?
Even before the debate, this was the week Gingrich became target No. 1. There was Ron Paul's blistering attack ad accusing Newt of serial hypocrisy.
UNIDENTIFIED MALE: He's demonstrating himself to be the very essence of the Washington insiders.
KARL: From the Romney super PAC.
UNIDENTIFIED FEMALE: The Gingrich record, 30 years in Washington, flip-flopping on issues.
KARL: And from Romney himself.
ROMNEY: I have been married to the same woman for 25 -- excuse me, I'll get in trouble -- for 42 years.
KARL: A not subtle reminder that Gingrich is the guy who has been married three times.
In Iowa, so they say, it comes down to the ground game. How is that looking? If you want evidence that Romney has not taken off here in Iowa, look no further than this. His Iowa state headquarters. They won't let us in. But looking in, there's nothing doing.
Over at Gingrich headquarters, we found them still setting up. Where's the energy? With Ron Paul. His office is smaller, but buzzing with activity.
As for President Obama, he took a populist turn this week with a speech in Kansas. Even if he seemed to forget for a moment where he was.
PRESIDENT BARACK OBAMA: It's great to be back in the state of Texas -- uh-oh. State of Kansas.
KARL: He was at no loss of words, however, when asked to respond to Republicans who say he appeases America's enemies.
GINGRICH: Consistently engaged in appeasement.
FORMER SEN. RICK SANTORUM, R-PA., PRESIDENTIAL CANDIDATE: Appeasement.
ROMNEY: Appeasement strategy.
OBAMA: Ask Osama bin Laden and the 22 out of 30 top al Qaeda leaders who have been taken off the field whether I engage in appeasement.
KARL: Trending, Newt, up. He's peaking at just the right time. Donald Trump, down. He offers to host a debate in Iowa and almost all of the candidates turn him down. Rick Perry down. Another oops. Who was that Supreme Court justice?
PERRY: Uh -- not Montemayor.
UNIDENTIFIED FEMALE: Sonia Sotomayor.
KARL: Bachmann, up. The debate her best day since the Ames straw poll.
KARL: And those hoping for Newt Gingrich to implode last night were sorely debated. He faced his first debate as the prime target of everybody else's attacks, and Christiane, he emerged unscathed.
AMANPOUR: Jon, thanks. And you'll be back with us in a moment. We'll talk more about all of this.
But right now, let's bring in the moderators of last night's debate, Diane Sawyer and George Stephanopoulos. Good to see you both this morning. It was a long night for you all.
Diane, let me ask you. Viewers were really expecting a rumble. How do you think it stacked up in the fisticuffs department?
DIANE SAWYER, ABC NEWS: You know, I think they came to engage, and they knew they had to, 23 days now until voting begins. But as Jon was saying, it was Newt Gingrich who was in the testing zone last night. And George was telling me that the Democratic National Committee this morning has already decided to target him, which means they think he survived it and survived it well.