The remaining Republican presidential candidates treated Jon Huntsman's endorsement of Mitt Romney as he bowed out of the race Monday much they way they treated Huntsman during his candidacy -- with barely a glance.

"I like Jon Huntsman. I actually got a chance to meet him and his wonderful wife and family and I wish him the very, very best, and he brings something to the table. But this is a race about who's going to be the strong conservative against Barack Obama," Rick Santorum told Fox News.

With Huntsman gone and with Fox News, The Wall Street Journal and the South Carolina Republican Party literally setting their debate stage Monday night with one less lectern, many pundits and voters  -- and even a candidate -- agree that should Romney pull of the hat trick this Saturday in South Carolina and go 3-0 in the early GOP contests, it could be very tough to stop him

The race is down to five now, which means four are tweaking their strategy to undo Romney's substantial lead in the polls, both in South Carolina and across the nation.

Ahead of Monday night's pivotal debate in Myrtle Beach, the candidates courted activists at a nearby Tea Party convention and a Faith and Freedom Coalition.

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The two groups represent a large segment of South Carolina's Republican Party -- social and fiscal conservatives -- and the events offered the candidates plenty of opportunity to smack around the front-runner and one another.

"I need your help to every person across the state to say to them: Any conservative who votes for anyone but Newt helps elect a moderate as the nominee. And therefore we need to get everybody -- if every conservative votes for me, we will win on Saturday by a huge margin, it is that simple," Gingrich told an enthusiastic crowd of about 150 Tea Party Patriots.

"If we are not a moral and religious nation, it doesn't work," said Ron Paul, quoting President John Adams in a speech to the Faith and Freedom Coalition. "Where have we ever been taught whether it's good economics or good religious values or good Christian values that we're supposed to spend, spend, spend, consume consume, consume, borrow, borrow, borrow and then inflate the currency? The Bible says we're supposed to have honest currency and that we're not supposed to print the money."

Heading into Monday night's debate, the candidates have difficult tasks ahead. Rick Perry, who's ranked last in the polling, now that Huntsman has dropped out, is courting evangelicals using the sermonizing skills that made him an attractive candidate before he entered the race.

Grabbing the sides of his head and thickening his drawl, the Texas governor told the forum audience that he would bring religion back to the public square if they help send him to Washington. He also got emotional discussing his wife, Anita, and his future in the race.

"If I had to walk away from all this, if she is walking with me, I'll be OK," he said in an unstated acknowledgement that his campaign may not last much longer.

Santorum, who has emerged in a Fox News poll as the "true conservative" to a plurality of voters, is taking an opposite tack. He is not only building his evangelical base, he is arguing that across-the-board, he is best representative of the values Republicans want and can win.

"The case for Romney is that he's somehow the best to win the general election, as your Fox poll shows. And I'm just saying that's simply not true. There's no record of Governor Romney being able to appeal to anybody," Santorum told Fox News, pointing to polls that show him faring as well as Romney against President Obama in several swing states.

"If you look at the key states, the industrial Midwest, that's my wheelhouse," Santorum said, adding that the Iowa caucuses will be certified in the coming day, and it's perhaps early for Romney to claim a 2-0 win since Santorum was only eight points behind him in the first-in-the-nation vote.

Romney has declared victories in the only two contests of the campaign thus far, the Iowa caucuses and New Hampshire primary earlier this month. Gingrich has conceded that the former Massachusetts governor will likely be the party's nominee if he is similarly victorious in South Carolina.

Romney is the leader in the public opinion polls in South Carolina, although his rivals hope the state's high 9.9 percent unemployment rate and the presence of large numbers of socially conservative evangelical voters will allow one of them to slip by him.

Santorum and Perry joined Gingrich in targeting the front-runner, who signaled Monday he will comply with tradition and release his tax returns if he becomes the Republican nominee.

For Romney, he needs to withstand the constant barrage. He attended the faith coalition "tent revival" and hit many of his talking points on social issues, like gay marriage and abortion. 

Whether it went over well could not be determined by the polite applause, something that Tea Party activist Jenny Beth Martin, co-founder of Tea Party Patriots, said is to be expected in the state.

"It's the South and ... we're just kind of a little more polite, I think," she said of her group's refrain from bashing the front-runner, even if he's not these voters' first choice.

For the candidates, though, the barrage of TV commercials, mail and other advertising blanketing the state is doing that instead. Santorum complained Monday morning that attacks launched against him by a political action committee supporting Romney was spreading lies. He called on Romney to ask the group to edit or remove its ads from the air.

That attack on Santorum is patterned after one that helped send Gingrich into a nosedive in the polls in the final weeks of the Iowa caucus campaign. Gingrich made similar demands on Romney to rein in his supporters but was ignored. When the tables were turned and a 28-minute film about Romney's tenure at Bain Capital was released, Gingrich said if anything's wrong with it, the producers of the film, who are independent of his campaign, should remove any inaccuracies.

The producers have said they have nothing to remove.