Charleston, in the heart of South Carolina’s 1st District, is a long way from the Appalachian Trail.

That’s good news for former South Carolina Gov. Mark Sanford, who looks poised to launch a comeback bid for his old House seat. The Republican looks to be the instant front-runner in the special election to fill the seat of now-Sen. Tim Scott in the coastal, safely Republican district.

Known as a fiscal conservative during his six years in the House and eight years as governor, Sanford is best known nationally for disappearing from the state for days in 2009 and then admitting to an extramarital affair with a woman from Argentina. He had told staff he was hiking on the Appalachian Trail.

His affair is almost certain to be a thorny issue with socially conservative primary voters but likely not enough to stop him from being one of the top two finishers in the March GOP primary. If no candidate gets more than 50 percent of the vote, a runoff will be held in April.

“In spite of his negatives, Mark would be almost certain to get enough votes in a crowded field to be in the runoff,” longtime South Carolina GOP consultant Richard Quinn Sr. said . “Of course, winning the runoff is a different matter.”

Insiders said a handful of ambitious Republicans are seriously considering the race. Along with Sanford, top potential candidates include state Sen. Larry Grooms and state Rep. Chip Limehouse. High school teacher Teddy Turner (the son of entrepreneur Ted Turner) is definitely running. Official filing begins Jan. 18 at noon.

Jenny Sanford, the former governor’s ex-wife, told CQ Roll Call last year she was considering a run. But insiders now believe she probably won’t pull the trigger on a bid. Jenny Sanford didn’t return requests for comment Thursday.

Mark Sanford would begin any race with two huge advantages over other potential candidates: Most South Carolinians already know who he is, and he has access to a wide and deep fundraising network.

He has about $120,000 in his dormant federal account and is expected to be able to raise a lot of money quickly.

To be successful in a crowded field, other candidates in the race will probably have to focus on building up their own profile, as opposed to tearing down Sanford.

And it won’t be cheap to do that. The district, reconfigured after the decennial redistricting process, stretches along the coast from Hilton Head Island to north of Charleston. About 80 percent of the district is in Charleston’s media market; the rest is in the Savannah, Ga., market.

Grooms told CQ Roll Call he was considering running and said he thought a viable candidate would have to raise at least $300,000 and probably $500,000 in the sprint of a race. Ticking through his accomplishments as a legislator, he trumpeted his conservative bona fides.

“I have a consistent record of being a conservative,” he said. “I’ve never compromised my principles.”

He said he thought Sanford’s behavior as governor would likely be an issue, and not just his personal shortcomings, but also his behavior as an executive.

But it remains unclear just how much Sanford’s issues will actually sway voters — and whether they’d be willing to forgive him.

The attack on Sanford from some candidates might focus more on his record from his eight years in Columbia and not accomplishing enough there, politicos in the state said.

“It’s not a particularly socially conservative district,” one South Carolina Republican operative said. “I think it’s going to be a referendum on Sanford’s results as governor.”

A Sanford aide noted the former governor’s record of fiscal conservatism, not just during his time in Columbia, but during his six years in Congress.

“At a time when too many Republicans are selling out in Washington, D.C.,” the aide said, “here’s a guy who will take on the fiscal crisis as a true conservative.”

Republican Gov. Nikki R. Haley signed an order this week for the primary to be held on March 19; a runoff, if no candidate gets more than 50 percent of the vote, on April 2; and a general election on May 7.

Sanford served in the House from 1995 until 2001. He served as governor from 2003 to 2011.

Sanford declined a request for an interview, but the aide said he continues to seriously consider a bid and is expected to make a decision soon.