Palmetto State Republican Reps. Jeff Duncan and Mick Mulvaney backed state Sen. Larry Grooms on Thursday for the GOP nomination in the 1st District special election.

Grooms, who faces 15 opponents including former Gov. Mark Sanford in a March 19 primary, will likely receive a major boost from their endorsements.

GOP insiders see Grooms as ideologically similar to Sanford — very conservative — but without the former governor’s political baggage. While governor in 2009, Sanford infamously disappeared from the state for days and then admitted to an extramarital affair with a woman from Argentina.

Still, Sanford is well-known in the district, and Republicans view him as the front-runner in the race to replace now-GOP Sen. Tim Scott.

Duncan and Mulvaney, both conservative members elected in 2010, praised Grooms in a statement from the candidate’s campaign.

“It’s important to ensure that the person who replaces Tim Scott be a reliable conservative, a proven fighter and a leader who will join our mission to cut wasteful Washington spending,” Duncan said. “I’m convinced the best person for the job is Larry Grooms.”

In another statement from the Grooms campaign, Mulvaney added: “Larry’s brand of conservatism, leadership and strength will serve South Carolina and the 1st District well in Congress.”

No candidate is expected to get more than 50 percent of the vote in the primary, so the top two finishers are likely to head to an April 2 runoff.

The GOP nominee will face Elizabeth Colbert Busch, the sister of comedian Stephen Colbert, in all likelihood. She’s the favorite to win the Democratic nomination.

The general election will be May 7.

CQ Roll Call rates the race as Likely Republican.