South Carolina Governor Mark Sanford, whose mysterious disappearance last Thursday prompted national headlines, acknowledged Wednesday afternoon that he had an extramarital affair.
"I've been unfaithful to my wife, and I developed a relationship with what started as a dear, dear friend from Argentina," he said, breaking down in tears.
Sanford returned from a trip to Buenos Aires Wednesday morning. He told reporters he was "obviously not" alone there.
Asked if he was separated from his wife, Sanford said, "I guess in a formal sense we're not."
But Jenny Sanford put out a statement following the press conference saying she asked her husband to leave two weeks ago as part of a "trial separation" in order to "maintain my dignity, self-respect, and my basic sense of right and wrong."
Read more of Jenny Sanford's statement>.)
The governor, who was first elected in 2002 and is now in his second term, said that he would resign as chair of the Republican Governors Association. The RGA announced that Gov. Haley Barbour of Mississippi will replace Sanford as chair, effective immediately.
Sanford said he and his wife were trying to "work through" the situation, and that his wife has known about the affair for about five months.
"I've let down a lot of people," Sanford added. "That's the bottom line."
"Sanford's tearful admission of an extramarital affair comes on the heels of Sen. John Ensign's admission last week, and he is the second potential 2012 presidential candidate to announce such a revelation," said CBS News Political Director Steve Chaggaris. "As in the case of Ensign, it's safe to say that Sanford's future as a presidential candidate is all but over."
Sanford's office initially explained Sanford's disappearance from the state by saying the governor was hiking on the Appalachian Trail.
Upon arriving at Hartsfield-Jackson International Airport this morning, the Republican governor acknowledged to The State newspaper that he had been in Buenos Aires.
The governor said in a statement following his remarks Wednesday that he "misled" his staff about his whereabouts, "and as a result the people of South Carolina believed something that wasn't true."
"I want to make absolutely clear that over the past two days at no time did anyone on my staff intentionally relay false information to other state officials or the public at large," he added. "What they've said over the past two days they believed to be true, and I'm sorry to them for putting them in this position."
"Once again, Americans have another reason to throw their hands up and say, 'There's another politician who couldn't keep it in his pants, and who abused the public trust,'" said CBS News Chief Political Consultant Marc Ambinder. "Confidence in political institutions is as low as it was after Watergate, and the less confidence the public has in politicians, the less competitive elections will be; fewer good people decide to run for office, and the cycle perpetuates." (Read more from Ambinder on the political fallout from the affair>.)
The State newspaper Wednesday afternoon published emails between Sanford and the woman with whom he had the affair. One of Sanford's missives reads, in part: "You have a level of sophistication that so fitting with your beauty. I could digress and say that you have the ability to give magnificent gentle kisses, or that I love your tan lines or that I love the curve of your hips, the erotic beauty of you holding yourself (or two magnificent parts of yourself) in the faded glow of the night's light." (Read more on the emails here>.)
Sanford, who is 49 years old and has four sons, asked Wednesday afternoon for a "zone of privacy" around himself and his family.
He said the extramarital relationship began innocently and that he had initially counseled the woman involved, who had been separated when she met Sanford, to get back together with her husband.
Sanford was not joined by his wife (pictured at left) in making the announcement Wednesday.
The governor has been one of the most prominent Republican voices opposing President Obama's federal stimulus package, and has won praise from conservatives for his position. He unsuccessfully fought in court to turn down a portion of the money allocated to his state.
In her statement, Jenny Sanford said her husband "has earned a chance to resurrect our marriage."
"This is a very painful time for us and I would humbly request now that members of the media respect the privacy of my boys and me as we struggle together to continue on with our lives and as I seek the wisdom of Solomon, the strength and patience of Job and the grace of God in helping to heal my family," she said.
Photo Essay: Political Sex Scandals