Rep. Chris Lee of New York abruptly resigned Wednesday evening, hours after a gossip Web site reported that the married Republican had allegedly sent flirtatious e-mail messages and a shirtless photo of himself to a woman he met online.

Lee experienced his fall from grace in a single afternoon, undone at the speed of the digital age. At lunchtime Wednesday, he was an obscure but promising second-term congressman. Then, at 2:33 p.m., the Web site Gawker posted an alleged e-mail exchange between a man who used Lee's name - but identified himself as a divorced lobbyist - and an unidentified woman. Gawker reported that the two had met through the personals section of Craigslist.

After that, the familiar cycles of a Washington sex scandal were compressed into a blur of tweets and news alerts. There was confusion, a hint of denial, then a pledge from Lee to "work it out" with his wife.

By 6 p.m., a clerk was announcing Lee's resignation in the House chamber.

"I regret the harm that my actions have caused my family, my staff and my constituents," Lee said in a statement. "I deeply and sincerely apologize to them all. I have made profound mistakes and I promise to work as hard as I can to seek their forgiveness."

Lee's statement did not confirm or deny any specific allegations from the Gawker report.

Lee, 46, elected from a district in western New York, was just beginning his second term in Congress. He had been a successful businessman and was known as an up-and-coming Republican voice on financial issues.

This term, he was given a coveted spot on the Ways and Means Committee, which writes tax laws. That was considered a quick rise for a new House member and a sign that he had backers in the GOP establishment.

"Clearly, that doesn't come without somebody loving you somewhere," New York Republican consultant Mike Collins said.

In New York, Lee was known for bringing his wife and young son to campaign events. He had a mostly conservative record during his time in Congress, though on a number of issues he broke with his party; he recently voted with Democrats on an overhaul of the nation's food-safety system and the Children's Health Insurance Program.

Republican consultant Jim Derderian, who worked with Lee on manufacturing and technology issues, said he had a rare talent for deconstructing complex subjects.

"It's a loss to Congress in that respect, because he showed an ability that not many have," Derderian said. "I think it's a shame that that type of perspective - combined with energy - is no longer at our disposal."