Video: Huckabee: 'you will see the gates of Hell' | Hillary race gaffe could be costly

The wide-open and unpredictable Republican presidential race moved to religiously conservative South Carolina last night with a debate dominated by Iran and Ronald Reagan.

The five candidates still in the running, holding a debate in a state whose primary on Saturday January 19 could determine the nomination, argued who best embodied the legacy of Ronald Reagan and talked belligerently about Tehran.

John McCain, boosted by his comeback victory in New Hampshire on Wednesday, and Mitt Romney, severely damaged after losing the first two nominating contests, also went after each other ahead of Tuesday's primary in Michigan, a showdown that could kill off either campaign.

Mr McCain, who emerged from the debate unscathed, received a further boost with new polls showing him leading in both Michigan and South Carolina.

South Carolina has a Republican electorate heavy with conservatives and evangelicals and is also home to many military bases. It is shaping up once again to be a critical contest in the party's nomination battle. Since it gained its first-in-the South status in 1980, no Republican has received the party nomination without winning the state.

A victory there for Mike Huckabee, the former Arkansas governor and onetime Baptist minister who rode to victory in Iowa on the support of evangelicals, would confirm his status as a serious national contender. He is staking much on victory in the Palmetto State, where his Southern, evangelical credentials are finding fertile ground.

Mr Huckabee has faced grave doubts about his foreign policy experience, his greatest vulnerability, but got one of the biggest cheers of the night when asked about the incident last week when Iranian boats swarmed US navy ships in the Strait of Hormuz.

Asked whether the American commanders on the scene were right in not attacking the Iranian boats, Mr Huckabee said he backed their decisions, before warning Iran: "Be prepared, first, to put your sights on the American vessel. And then be prepared that the next thing you see will be the gates of Hell, because that is exactly what you will see after that."

Fred Thompson, the former Tennessee senator and Law & Order star who is banking all on victory in South Carolina to revive his campaign, said of the Iranian boat crews: "I think one more step and they would have been introduced to those virgins that they're looking forward to seeing." The crowd cheered.

Rudy Giuliani, the former New York mayor, said: "I think an incident like this reminds us that we shouldn't be lulled into some false sense of confidence about Iran."

Mitt Romney, the former Massachusetts governor seeking to become America's first Mormon president, said: "I believe it was a very serious act."

All the candidates sought to invoke Mr Reagan, a conservative hero, to boost their message. Mr Thompson accused Mr Huckabee of betraying the former president's principles of low taxes and hawkish national security policies when Arkansas governor. "This is a battle for the heart and soul of the Republican party and its future," he said.

Rudy Giuliani, the former New York mayor who is basing much of his campaign on his performance after the September 11 attacks, and the issue of terrorism, said: "We are different times, but Ronald Reagan's principles apply now." He said America must face down its enemies.

The next showdown in the Republican race is in Michigan on Tuesday, a state vital to Mr McCain and Mr Romney. Mr Romney, whose father was governor there, must win it to keep his campaign alive. Mr McCain believes he can finish Mr Romney off if he wins it. But he also badly needs victory to keep his extraordinary comeback going. His New Hampshire victory was achieved after his campaign fell apart in the summer.

Mr Romney accused Mr McCain of giving up on people who had lost their jobs in the economically depressed Michigan, after the Arizona senator said at rallies on Thursday that some lost jobs will never return.

Mr McCain, who at times can barely conceal his contempt for Mr Romney, said he was simply telling voters the truth.

Mr Giuliani is staking his candidacy instead on victory in Florida in January 29, which he hopes will propel him to big wins on February 5, "Super Tuesday", when more than 20 states vote.

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