Five battles to watch at the South Carolina debate

We’re down to the final five.

With Jon Huntsman Jr.’s decision to go no further, the GOP presidential field has been pared down to front-runner Mitt Romney and four others desperate to find some way to slow his momentum.

South Carolina remains the best hope for Newt Gingrich, Rick Santorum, Ron Paul or Rick Perry to pull off an upset. But to do it, they’ll need to knock Romney off his game at Monday evening’s debate in Myrtle Beach, S.C.

There’s risk involved. Gingrich and Perry have found that some conservatives haven’t warmed to their attacks on Romney’s work at Bain Capital. Perhaps the No. 1 question leading up to the debate, sponsored by Fox News, is whether those two candidates will hit Romney hard on Bain.

In honor of the remaining five candidates, here are five battles to watch in the debate, which begins at 9 p.m. Eastern time. (And if you miss this one, there’s another debate in three days.)

1. Gingrich versus Bain: After pledging to not back away from his claims that Romney destroyed jobs while at Bain, Gingrich suddenly got cuddlier on the subject Sunday. So which Newt will we see this evening? Fire-breathing, Bain-hating Newt or let’s-all-get-along Newt?

2. Santorum versus Romney: Santorum is one candidate who has found fault with the Bain line of attack, so expect him to instead play to the values voters in South Carolina by playing up his credentials on abortion and other social issues while suggesting Romney is squishier on those matters. Santorum has also complained about being hammered by a pro-Romney “super PAC� in South Carolina.

3. Romney versus Romney: In the absence of serious conflict, it’s always worthwhile to see whether the front-runner, with the wind at his back, makes any mistakes or falls into any traps like the $10,000 bet (not good) or his answer in New Hampshire about making contraception illegal (good).

4. Paul versus Santorum: As they say in sports, these guys flat don’t like each other. It probably started when Santorum was blasting Paul over Iran, but now the back and forth has gotten more intense as the two compete for voters. Paul’s campaign lately has been airing attack ads against Santorum, suggesting he was a corrupt Washington insider when he served as a senator from Pennsylvania.

5. Perry against the world: As the hour grows late for the trailin’ Texan, it’s always entertaining to see what attention-seeking Hail Mary he’ll throw next. Over the weekend, it was his suggestion that the Marines videotaped urinating on a dead Taliban solider were just kids who didn’t know any better that raised eyebrows. And of all the candidates, he’s the most likely to continue to Bain-bash. If Perry doesn’t reverse his fortunes soon, he’ll be following Huntsman -- and Tim Tebow -- out the door.