Former South Carolina governor Mark Sanford (R). (Chip Somodevilla/Getty Images)

It's official (or will be tomorrow): Former South Carolina governor Mark Sanford (R) is running in the special election for the state's 1st district.

"Officially we’re going to announce tomorrow, and then it’s off to the races," he told the National Review.

The House seat was left vacant earlier this month, when Rep. Tim Scott (R) was appointed to fill the Senate seat vacated by former senator Jim DeMint (R). A special election primary will be held March 19 with a general election on May 7.

Sanford told the conservative magazine that he had thought his political career was over but that "miraculous events" had brought him back. Sanford held the 1st House seat from 1995 to 2001.

In the interview, Sanford attempts to preempt some of his critics' arguments, contending that ethics charges against him were overblown. In the wake of his public confession of an affair with an Argentine woman, the former governor was charged with 37 ethics violations and agreed to pay a $74,000 fine. He is now divorced and engaged to his former mistress.

"I’m not questioning my failure in certain areas, I certainly mishandled things in that chapter of life," he said. "Okay, the guy made a mistake. Let’s look at the magnitude of that mistake and let’s judge it in the light of other areas where he hasn't wavered, as a champion of the taxpayer and reforming government and common sense solutions."

Sanford's ex-wife, Jenny Sanford, announced Monday that she would not run for the seat.

The ex-governor has a decent shot at victory, despite his past foibles. He knows the territory from his time in the House, and a crowded field in a low-turnout race means anything can happen.

Other declared or possible candidates include state Sen. Larry Grooms; state House Majority Whip Jimmy Merrill; and state Rep. Peter McCoy.