In one of the liveliest exchanges, former Massachusetts Gov. Mitt Romney deplored rival Sen. John McCain's stand on illegal immigration. Romney said McCain's plan for a "special pathway" to citizenship could turn out as "bad" as his signature campaign- finance reform law, which is widely reviled among conservatives.

The crowd of invited guests at the University of South Carolina roared its approval, but [Ron Paul] did not back down. "I believe very sincerely that the CIA is correct when they teach and talk about blowback," he said. "They don't come here to attack us because we're rich and we're free. They come and they attack us because we're over there."

Sen. Sam Brownback of Kansas, however, reiterated his opposition to Bush's Iraq policy and said it was important to reach a consensus in Washington for there to be any success in Iraq. "I think we've got to pull together here to win over there," he said. "I mean, we've got far too many divisions in this government here. And we will win if we can pull together."