Hampton learned of wife's affair with Ensign in text message, he says

WASHINGTON -- Doug Hampton, the Nevada man whose wife had an affair with Sen. John Ensign, said he discovered the relationship after intercepting a text message around Christmas in 2007.

"How wonderful it is. ... Scared, but excited."

Hampton recounted the text message during an interview broadcast Monday on ABC's "Nightline." The interview covered a lot of ground already made public since Ensign, R-Nev., acknowledged the extramarital affair in June, but it provided new details about how the affair was discovered as well as the senator's reaction when Hampton confronted him.

The acknowledgment of the affair has led to a huge fall from grace for a man many viewed as a rising star within the GOP. Ensign is now fighting to complete a second term in office that continues through 2012.

The Hamptons and the Ensigns had been close family friends for years. Hampton told "Nightline" that he confronted Ensign when both families were at a Christmas Eve gathering.

"John cries like a kid. Puts his head in his hands, cries like a little boy," Hampton said, adding that he heard remorse and panic in his friend's voice but now believes it was disingenuous.

Hampton continued to work for Ensign. He said the two went on a trip to Iraq in February 2008. He said he was having problems with his telephone and asked to borrow Ensign's to call his wife. He said Ensign scrolled to a listing for Aunt Judy instead of Cindy Hampton. "And then I realize, 'Wow, wow, something is seriously wrong,'" he said, concluding that the affair was still going on.

Hampton said in the interview that he isn't going away quietly and believes Ensign abused his power in pursuing the affair.

Ensign's legal team has said it's confident that all laws and ethics rules were followed in the case, which includes Ensign helping Hampton gain employment with a lobbying firm and the senator's parents giving the Hamptons nearly $100,000 that they described as a gift.

In a statement to ABC News, Ensign said the allegations are "full of half truths and untruths." He said he would cooperate fully with any investigation.