Michigan comes next on the primary calendar, but Republican presidential candidates are weighing their strategies for South Carolina as they briefly detour there on Thursday to take their seats at a FOX News debate in Myrtle Beach.

The debate comes as a couple of the GOP candidates -- Mitt Romney and Rudy Giuliani -- have essentially given up on the Palmetto State and instead are trying for strategic advantage elsewhere. Conversely, Fred Thompson is staking his entire race on a bravura performance in South Carolina.

The face-off, leading to the first-in-the-South primary on Jan. 19, will give the six candidates the chance to set themselves apart and reach out to South Carolina voters at a time when resources are spread thin across the country and no real front-runner has emerged.

Watch the Republican presidential primary candidates debate in Myrtle Beach, S.C., live on FOX News Channel and FOXNews.com at 9 p.m. ET.

A FOX News-Opinion Dynamics poll shows Mike Huckabee, John McCain and Romney all in contention for the top position in the state, with McCain experiencing a bump from his New Hampshire primary win on Tuesday.

The poll, taken overnight of 500 likely South Carolina GOP primary voters, showed McCain with 25 percent, Huckabee with 18 percent, Romney with 17 percent and Thompson with 9 percent. Giuliani and Texas Rep. Ron Paul each took 5 percent in the poll. The margin of error was 4 percent.

Click here to see the results from the FOX News South Carolina poll.

The latest South Carolina poll averages from RealClearPolitics.com show Huckabee holding onto a wide lead there. The averages have the former Arkansas governor with 27.8 percent of the vote, McCain with 22.5 percent, Romney with 16.5 percent, Thompson with 9.3 percent, Giuliani with 7 percent and Paul with 5 percent.

Romney's South Carolina campaign is lowering expectations for the former Massachusetts governor, whose team decided to pull ads from the state and focus on Michigan, where he is supposed to be a favored son since his father, George Romney, was governor there in the 1960s.

Campaign aides in South Carolina say Romney plans to let Huckabee and McCain "slug it out" on the debate stage Thursday night, in hopes one will mortally wound his campaign ahead of the South Carolina primary. A Romney aide gave FOX News the very strong impression on Thursday that if Romney doesn't win the Michigan primary next Tuesday, he could drop out of the race.

Giuliani's campaign has pulled all of its paid staff out of South Carolina as it concentrates its efforts in Florida, where he has spent most of his time. The decision to pull the staff comes in the wake of a similar decision to pull paid staffers out of Michigan.

Over the course of the last six months, Giuliani has visited South Carolina about a dozen times. He plans to return to Florida on Friday for campaign events and will be conducting a three-day bus tour of the Sunshine State starting on Sunday.

In Florida, two new ads for the the former New York City mayor are running, including one that highlights the tax cut plan he announced in Melbourne, Fla., on Wednesday and another that discusses "what's at stake" in the election.

Click here to see the Giuliani ad "Super Bowl."

Responding to skeptics who question Giuliani's strategy of overlooking the earliest voting states, the narrator in the ad, says: With pundits and politicos handicapping the campaign like the Super Bowl, it's easy to lose sight of what's at stake. An economy in peril. A country at war. A future uncertain.

"The media loves process. Talking heads love chatter. But Florida has a chance to turn down the noise and show the world that leadership is what really matters," the narrator says.

Other GOP hopefuls have taken different approaches to the Palmetto State. Huckabee headed immediately to South Carolina following a third-place finish in New Hampshire. McCain, coming off his Granite State victory, is trying to balance his time between South Carolina and Michigan, where he is also currently polling at the top of the pack.

Paul, who placed fifth in New Hampshire above Thompson and fifth in Iowa ahead of Giuliani, has been developing his get-out-the vote effort in Michigan and was to attend a rally of South Carolina supporters after the debate.

Thompson has staked his campaign on South Carolina after bypassing New Hampshire and finishing last.

"South Carolina is home territory man," the former Tennessee senator told FOX News Radio, saying he's not worried state polls still show him trailing. Having set up South Carolina as a firewall, Thompson is looking for a comeback as his candidacy has steadily lost traction in the polls since officially launching in September.

"We've been going all over the state in the bus, getting out and doing a little retail politics," said Thompson, who's playing up his support for gun rights and his Southern roots. "We're the consistent conservative ... We're drawing the line in the sand in South Carolina."

By midday Thursday the area around the Myrtle Beach Convention Center had turned into a political carnival. The six Republicans were greeted by giant sand sculptures of their heads -- a Mount Rushmore-like rendering of the big names in the 2008 GOP race.

"Nobody gets to (the White House) unless he comes through South Carolina," Huckabee asserted at Furman University in Greenville, S.C. Wednesday night. "I want to let you know that I'm here in South Carolina because I want to win the White House, and to do that, I want to win South Carolina and I'm going to need your help to get there."

Huckabee was in his element as he returned to the social conservative themes that helped him win Iowa a week earlier. Shedding the economic conservative populist messages he picked up in New Hampshire, the Southern Baptist pastor returned to anti-abortion, protect-the-borders, build-the-military themes that play strong to the huge populations of evangelicals and veterans in the state.

Huckabee energized the crowd with folksy yarns and a jam session where he played bass.

While many evangelicals have never warmed to McCain, the Vietnam War POW is hoping to appeal to moderates and independents and avoid his undoing in 2000, when he lost South Carolina after winning New Hampshire.

Asked in Greenville Thursday about the possibility of the 2000 race haunting him, McCain said, "I think people look forward, I don't think they look back."

McCain is also trying to emphasize his foreign policy credentials by stressing that the troop surge in Iraq, which he supported, has paid dividends.

He released a statement Thursday marking the one-year anniversary of President Bush announcing the surge.

"I had long argued that a change in course in Iraq was critical to achieve success there," McCain said in the statement. "Today, thanks to the tremendous leadership of General Petraeus and the bravery of our troops, the surge is working."

FOX News' Carl Cameron, Shushannah Walshe, Mosheh Oinounou and Serafin Gomez and The Associated Press contributed to this report.