In their most contentious debate yet, the eight Republican contenders for the White House were forced to tackle tough questions on Iraq, torture and illegal immigration.
And in another indication the Republican nomination is truly up for grabs, their toughest interrogators were each other.
The CNN/YouTube sponsored debate in St. Petersburg, Fla., kicked off with a contentious and angry exchange between front-runners Rudy Giuliani and Mitt Romney on immigration.
"The reality is that New York City was not a sanctuary city," former New York Mayor Rudy Giuliani said in response to a question posed by Ernie Nardi of Dyker Heights in Brooklyn, New York.
Romney, the former governor of Massachusetts, quickly took issue with Giuliani's contention.
"[New York] called itself a sanctuary city. And as a matter of fact, when the welfare reform act that President Clinton brought forward said that they were going to end the sanctuary policy of New York City, the mayor actually brought a suit to maintain its sanctuary city status," Romney contended.
"It's unfortunate, but Mitt generally criticizes people in a situation in which he's had [by] far the worst record. … There was even a sanctuary mansion. At his own home, illegal immigrants were being employed, not being turned into anybody or by anyone."
That was a reference to Romney employing a landscaping company that employed illegal Guatemalan immigrants at his pink colonial mansion in Belmont, Mass.
Romney shot back, "I think it is really kind of offensive actually to suggest, to say look, you know what, if you are a homeowner and you hire a company to come provide a service at your home — paint the home, put on the roof. If you hear someone that is working out there, not that you have employed, but that the company has."
Moments later, Romney said, "Mayor, you know better than that," before adding this to the Brooklyn-born Giuliani, "If you hear someone with a funny accent, you, as a homeowner, are supposed to go out there and say, 'I want to see your papers?'"
Former Tennessee Sen. Fred Thompson also got into the act, going after Giuliani and targeting Romney as a flip-flopper.
"Gov. Romney supported the Bush immigration plan until a short time ago. Now he's taken another position, surprisingly," the actor-turned-politician declared.
Even more intriguing, Thompson took his free 30 seconds for his YouTube video to run an attack ad — the first one of the season — against Romney for once supporting abortion rights and former Arkansas Gov. Mike Huckabee, surging in Iowa, for having raised taxes.
"What's up with that?" asked debate moderator Anderson Cooper.
"I just wanted to give my buddies here a little extra airtime," Thompson dryly replied. "Listen, I mean, what do you mean what's up with it? These are their words."
Huckabee's rising star brought several incoming shots. He was asked about scholarships he supported for the children of illegal immigrants.
"This bill would've said that if you came here, not because you made the choice but because your parents did, that we're not going to punish a child because the parent committed a crime," Huckabee explained.