Image credit: Bruce Smith/AP Photo

Mark Sanford has overcome his past-for now. The disgraced former South Carolina governor ran a successful Republican primary campaign for the House seat he held in the 1990s, besting attorney and former Charleston County Council member Curtis Bostic Tuesday night in a runoff.

Sanford's win followed a 16-way first round of the GOP primary, in which he rose above a large and varied field of South Carolina politicos.

But more importantly, it followed nearly four years in the political wilderness. In 2009, Sanford revealed an extramarital affair with Maria Belen Chapur, now his fiancee, during one of the most memorable and strange political press conferences of the century, punctuated by personal openness and tears, after going AWOL for seven days, leading staff and public alike to believe he was hiking on the Appalachian Trail. It seemed he would never surface in politics again.

Sanford said as much, two years later: "No, I'm not," Sanford told Fox News' Sean Hannity in 2011, when asked if he was considering a return to politics.

It's difficult to say whether Sanford's win on Tuesday night was triumphant.

He took 57 percent to Bostic's 43 percent-a substantial margin, but perhaps not what one would expect of a former statewide officeholder with near-universal recognition in the district.

Forgiveness was an early theme in Sanford's campaign, featured in his first TV ad in the district, and Sanford will now test voters' forgiveness against Elizabeth Colbert Busch, the sister of Comedy Central host Stephen Colbert.

The question now becomes: Could Sanford blow it?

The First District favors Republicans, in a big way. No Democrat has represented it in Congress since 1981.

Still, Sanford brings his unique problems to the race.

Aside from the question of whether Sanford's highly public extramarital affair will damage his standing, particularly among female voters, one South Carolina Republican insider suggested to ABC News that voters would forgive his personal conduct-but not his "abandoning" the state while on his then-mysterious Argentinian trip.

Another South Carolina GOP politico, who worked for Sanford primary rival Larry Grooms, suggested Colbert Busch has a real shot.

"Yes, very much so," said Hogan Gidley, a former state party director and former consultant for Rick Santorum's presidential campaign. "She's well-known, she's well-liked and she's well-respected. It's just a political reality that it will be very difficult for Sanford to attack her in any way … [that] could trump party loyalty as a motivator. If it does you'll see the fiscal conservatives and social conservatives sending a loud message we are not just about winning, principals really do matter."

No poll has been conducted in the district that meets ABC's standards for reliability. Although Colbert Busch claims to lead Sanford both in horse-race polling and in favorability, based on a survey her campaign commissioned, she hasn't yet endured the withering attacks sure to come her way, almost certain to paint her as an Obama-loving liberal who lacks fiscal-conservative cred. The National Republican Congressional Committee is already criticizing Colbert Busch for her support for parts of the president's health law, although not yet in paid advertising. On top of that, Mitt Romney won the district handily over President Obama in the fall.

One South Carolina Republican questioned whether Colbert Busch's star power, and the attention that Democrats from other states will give her, would help or hurt her in a heavily Republican district.

Sanford will have until May 7 to tell voters about his opponent, as the focus now shifts from his own improbable comeback to a race against a Democratic opponent who, some think, could turn a deep red district blue.