After a week of sometimes indignant public denials and insistence that he was the victim of an Internet hacker, a weeping and stammering Mr. Weiner, 46, acknowledged at a news conference that he had sent the photo of himself in his underwear to the woman, a college student in Seattle.
The six-term congressman from Brooklyn said he had broken no laws and would remain in office, calling the matter an ?aberration from which I?ve learned.?
During an extraordinary 27-minute appearance, Mr. Weiner went on to describe a side of his life that he had kept secret from his closest confidants and family members, befriending young female admirers over the Internet and engaging in intimate sexual banter with them, sometimes sending them racy self portraits taken with his BlackBerry.
In one of the photographs, he is sitting bare-chested at his home computer, with a row of personal pictures behind him.
?Over the past few years, I have engaged in several inappropriate conversations conducted over Twitter, Facebook, e-mail and occasionally on the phone with women I had met online,? Mr. Weiner said.
The congressman said he had never personally met the women with whom he had corresponded. ?I don?t know what I was thinking,? he said. ?This was a destructive thing to do. I?m apologetic for doing it.?
Mr. Weiner?s political standing appeared in grave danger after his news conference. There was a striking absence of public expressions of support from his colleagues, and the House Democratic leader, Representative Nancy Pelosi of California, called for an ethics investigation into his conduct. ?I am deeply disappointed and saddened about this situation,? she said.
House ethics rules state that members should conduct themselves ?at all times in a manner that shall reflect creditably on the House.?
Mr. Weiner?s public confession was prompted on Monday when Andrew Breitbart, a conservative blogger and provocative critic of the left, followed through on a vow to publish photographs Mr. Weiner had sent to a woman online. As Mr. Breitbart began to unveil the photos one by one, from midmorning until early afternoon, Mr. Weiner?s staff seemed paralyzed, failing to answer questions or challenge the authenticity of the images.
In one of them, the congressman is pictured holding up a handwritten sign reading ?it?s me.? He had sent it to a 26-year-old woman in Texas after she had expressed skepticism that she was exchanging personal messages with Mr. Weiner.
In his remarks to reporters, he declined to characterize any of the specific exchanges with the women, saying he was respecting their privacy. ?This isn?t anyone else?s fault,? Mr. Weiner said. His news conference at a Midtown Manhattan hotel was a singular spectacle: the House?s most pugilistic liberal, known for skewering his rivals in YouTube-ready bursts of righteous anger, appearing on live television as a penitent, teary figure behind a spare wooden lectern.
He explained, in a soft, clinical tone, that the online relationships with the women had begun three years ago and that several of them began after he was married in July to Huma Abedin, a longtime aide to Secretary of State Hillary Rodham Clinton, in an elegant ceremony officiated by former President Bill Clinton.
While he emphasized his failings, Mr. Weiner strained to point out that there were lines he had not crossed. He stressed that he did not have physical contact with any of the six women and that he believed they were all adults.