Mark Sanford

"I've been unfaithful to my wife," said South Carolina Gov. Mark Sanford in 2009. "I developed a relationship with what started as a dear, dear friend from Argentina. It began very innocently as I suspect many of these things do, in just a casual e-mail back and forth in advice on one's life there and advice here. But here recently, over this last year, it developed into something much more than that."

Sanford resigned as chairman of the Republican Governors Association, after he admitted he had engaged in an affair with Mar?a Belen Chapur. He was later censured for misusing travel funds during the affair. His wife moved out of the governor's mansion and later filed for divorce.

Credit: Alex Wong