South Carolina Governor Mark Sanford, a rising GOP star, admitted an extramarital affair today at a live news conference in Columbia. The Governor has been out of town in what was said to be hiking trip on the Appalacian Trail, but as Sanford admitted today, was in fact a trip to Argentina to end an extramarital affair he has been having with a woman he has known for nearly a decade.

South Carolina Gov. Mark Sanford, his eyes red, admitted to having an extramarital affair Wednesday with an Argentine woman.

“I’ve been unfaithful to be my wife,” Sanford said at a state capitol news conference.

It began very innocently,” he explained, saying that developed into an adulterous relationship in the past year.

Sanford also announced that he has resigned as head of the Republican Governor’s Association, and calls have already begun for him to resign as the Chief Executive of the Palmetto state. A fiscal conservative star, Governor Sanford has been front and center in the national debate on stimulus and egregious spending, and had been considered a prime potential Presidential candidate for Republicans in 2012. With the news last week from John Ensign, Nevada GOP Senator, that makes the second potential GOP Presidential hopeful in two weeks that has had a campaign derailed by admissions of an extramarital affair.

With Sanford’s admission today, the GOP takes a hard hit losing a hero of fiscal conservatives, a man who stood up against President Obama’s overreaching, particularly the strings attached provisions of the federal stimulus legislation. The Governor took heat from the local and national media, and members of his own party in South Carolina for his decision to stand up against growing federal influence in his state budget. The falling of his star today is a sad day for Republicans, as it does not help the party clean up it’s public image and get itself back on the road to recovery.

Kudos go to Governor Sanford though for coming clean, admitting his mistake, seeking the forgiveness of his family, his friends, and his constituents in South Carolina. It takes a man to admit that on national television in front of a hostile group of reporters. Best wishes to Governor and Mrs. Sanford, and their children.