Mark Sanford holds edge ahead of Republican runoff in South Carolina

Former South Carolina Gov. Mark Sanford's opponent is showing some momentum in the closing days of the Republican primary campaign for the state’s open House seat — but it may be too late to help him win Tuesday's vote.

Attorney Curtis Bostic, who finished second to Sanford in a preliminary vote March 19, has secured some high-profile backing in the final week of the campaign.

Former Sen. Rick Santorum (R-Pa.) stumped with him last Wednesday in the district and conservative commentator Ann Coulter also endorsed him.

Coulter called Sanford the “Todd Akin of South Carolina” — a reference to the failed GOP Senate candidate in Missouri — because of scandal over the ex-governor’s past marital infidelities.

Bostic also has the support of Focus on the Family founder James Dobson, former Rep. Henry Brown (R-S.C.), who represented the Charleston-based 1st congressional district until 2010, singer and conservative activist Pat Boone, and more than 40 local pastors.

But Bostic, a social conservative and former Charleston county councilman, has a steep hill to climb if he is to mount an upset.

He finished a distant second in the first round of voting, with 13 percent, compared to Sanford’s 37 percent.

And despite the high-profile endorsements, there are no clear evidence Bostic has done much to rally the voters who backed other candidates in the first round of voting.

“It's Sanford's to win — he's a professional politician and knows how to run a race,” said Katon Dawson, a former head of the South Carolina Republican Party.

Just one of the 14 other Republicans who ran for the seat has backed Bostic, while six have endorsed Sanford.

Bostic emerged from first round of voting flat broke and has been able to spend only $40,000 on television during the runoff, while Sanford is flush with cash and has advertised heavily.

Those watching the race closely say Sanford remains the heavy favorite to win, but note that the likelihood of an extremely low turnout could play to Bostic’s advantage.

“It's two days after Easter, it's spring break in the low country, and neither one has a ton of extensive get-out-the-vote, I know for a fact,” Dawson said. “Still, it would be the surprise of the year if Curtis wins.”

A recent poll from the Democratic firm Public Policy Polling showed Sanford leading Bostic by 53 to 40 percent, though special elections and House primaries are notoriously hard to predict.

The winner of Tuesday’s runoff will face Democrat Elizabeth Colbert Busch in the May 7 special election, which was called after former Rep. Tim Scott (R) was appointed to the Senate.

Sanford touted his record as a fiscal conservative throughout the campaign. But he drew more attention for opening his political comeback with an apology tour — expressing contrition in media interviews and television ads for a 2009 extramarital affair.

The former governor admitted that year to telling his staff he was hiking the Appalachian Trail, while he was having an affair with an Argentine woman.

Sanford is now engaged to the woman and has repeatedly apologized for his past misdeeds.

His latest campaign ads have focused on his economic voting record while governor and in the House.

“Our message is the same it has been: Other people talk about stopping spending, and Gov. Sanford has actually done it,” said Sanford advisor Joel Sawyer.

Bostic has run a mostly positive campaign that has focused on his own conservative bona fides rather Sanford’s fall from grace.

Through much of the campaign, he passed up opportunities to attack the well-known former governor.

But he did take some shots at Sanford in debate last Thursday, calling him a "compromised candidate" and warning the GOP might lose the seat if he's the nominee.

But Bostic did very little to attack Sanford before that moment — or after.

During a televised Saturday debate, Bostic didn’t repeat his criticisms of Sanford’s infidelity, even after Sanford gave him an opening by talking about the sanctity of marriage as he explained his personal opposition to gay marriage.

“It is not to say every marriage makes it, but it is to say that is the ideal we are aiming for," Sanford said.

Bostic passed on the chance to raise Sanford’s affair, focusing instead on his own support of a federal constitutional amendment banning gay marriage.

“We still anticipate maintaining a positive campaign,” David O’Connell, Bostic’s campaign manager, told The Hill on Friday.

Bostic's campaign says he only attacked Sanford after the governor questioned the candidate for missing Charleston county council meetings — which Bostic says he could not attend because his wife was going through cancer treatment.

“The only time there was a bit of a dustup was only after Gov. Sanford viciously attacked Curtis Bostic's attendance record (on city council), which is shocking given his own record of attendance (as governor) … when Curtis was taking care of his sick wife at the time.”

- Sterling C. Beard contributed

An earlier version of this story incorrectly stated that Sanford was endorsed by three ex-candidates and was corrected at 8:50 a.m. on April 1.

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