COLUMBIA, S.C. — A splintered conservative vote in South Carolina could pave the way for Mitt Romney to win this week’s pivotal primary — a contest due to have one fewer candidate after the withdrawal of moderate Jon Huntsman.

Huntsman, a former governor of Utah, withdrew from the race today, campaign manager Matt David said. Huntsman endorsed Romney, aides said.

Before news of Huntsman’s decision broke Sunday, Romney’s other rivals wrestled with the likelihood that they’ll split the vote of South Carolina’s social conservatives.

“I think the only way that a Massachusetts moderate can get through South Carolina is if the vote is split,” said Newt Gingrich, portraying himself as the lone conservative with a “realistic chance” of beating Romney in the first-in-the-South contest.

Polls show Romney, the former Massachusetts governor who struggled to a fourth-place finish in South Carolina during his 2008 White House run, with a lead heading into Saturday’s vote. The state has a large population of evangelicals and other conservative Christians, and concerns arose four years ago about his Mormon faith.