With only two full days left before the first-in-the-nation New Hampshire primary, Republican candidates faced off as former Gov. Mitt Romney, fighting for his political life, accused Sen. John McCain of supporting "amnesty" for illegal immigrants, and sparred with former Gov. Mike Huckabee over his criticism of Bush administration foreign policy.
Sparks flew quickly in the debate, hosted by ABC News, Facebook and WMUR, the local ABC affiliate station.
Touching off a heated exchange between Huckabee and Romney, moderator Charles Gibson asked the Republican rivals, who sat in a semi-circle on a stage at St. Anslem's College in Manchester, N.H., if they agreed with President Bush's foreign policy.
Defending his previous criticism that the Bush administration's foreign policy is "arrogant" and a "bunker-mentality," Huckabee attacked his Republican rival, suggesting he had better foreign policy bona fides.
"When I made those statements, there were times that we gave the world the impression we were going to do whatever we wanted to do," Huckabee defended.
Romney shot back: "I don't agree that the administration suffers from an arrogant bunker mentality," referring to a claim Huckabee made in a recent article in Foreign Affairs.
"Did you read the article?" Huckabee asked.
"I did read the article. I read the entire article," Romney responded.
Then Huckabee accused Romney of switching positions on Bush's troop surge strategy in Iraq, arguing he had come out in favor of increasing U.S. troops in Iraq long before Romney.
"I supported the president on the war before you did," said Huckabee. "I'm not a person who is out there taking cheap shots at the president."
Romney fired back, accusing Huckabee of distorting his position.
"I also supported the troop surge," Romney said, "Don't try to mischaracterize my position."
"Which one?" Huckabee shot back. "It's not a personal attack, Mitt, because you also supported a timed withdrawal."
Jumping into the fray, Sen. John McCain, R-Ariz., argued that he alone among Republican presidential contenders criticized Bush's initial policy in the war on Iraq.
"We are succeeding now in Iraq. As we blame the president for the failed strategy, we should give him credit," McCain said.
Former Sen. Fred Thompson of Tennessee agreed that the United States went to war in Iraq with too few troops.
Former New York Mayor Rudy Giuliani said Bush "got the big decision of his presidency right ... when he put us on the offense against Islamic terrorists."
The candidates sat beside one another in a forum Gibson said he hoped would be more of a conversation rather a debate.
But the conversation turned explosive as the leading candidates in New Hampshire sought to draw distinctions.
Romney and McCain quickly began sparring on immigration, with McCain angrily denouncing the attack ads Romney has launched in the state that accused the Arizona senator of supporting "amnesty" for illegal immigrants.
"You can spend your whole fortune on these attack ads, but it doesn't make it true," McCain said.