The extraordinary confession at a packed Manhattan news conference was a remarkable turn of events for the brash Weiner, who conceded to a "hugely regrettable" lapse in judgment. House Democratic leaders tersely expressed disappointment and embarrassment, reflecting an erosion of support for the 46-year-old New York congressman and casting doubts on whether Weiner could hold onto his House seat let alone turn a once-promising political career into a 2013 bid for mayor.
Weiner insisted he had done nothing wrong and said he would fully cooperate with a House inquiry.
"People who draw conclusions about me are free to do so," Weiner said. "I've worked for the people of my district for 13 years and in politics for 20 years and I hope they see fit to see this in the light that it is."
But in a new twist, the married Weiner also acknowledged that he had engaged in inappropriate contact with six women over the course of three years through social networking sites like Twitter and Facebook and occasionally over the phone. He said he had never met or had a physical relationship with any of the women and was not even sure of their ages. He also said he had never had sex outside of his marriage.
The news conference, unusually blunt even by New York standards, went on nearly half an hour and capped a week of double-entendre, tabloid-headlines and late-night jokesters' snide comments. With eyes welling and voice breaking, Weiner fielded questions from dozens of shouting reporters as the cameras clicked.
Weiner said over and over that he had made "terrible mistakes" and done "a very dumb thing" for which he alone bore responsibility, and he apologized repeatedly to his wife, Huma Abedin, a top aide to Secretary of State Hillary Rodham Clinton.
"My wife is a remarkable woman. She's not responsible for any of this," he said. "I apologize to her very deeply."
Abedin did not attend his news conference, but Weiner said they would not be separating over the scandal.
Among the women Weiner contacted, Meagan Broussard, told ABC News that Weiner "friended" her on Facebook after she commented on one of his speeches posted online on April 20. They exchanged more than 100 messages, and Weiner constantly tried to steer the conversation toward sex.
"I don't think he's a bad guy. I think he's got issues just like everybody else," Broussard, 26, said in an interview aired Monday night.
During Weiner's news conference, the lawmaker confirmed that Broussard was one of the women with which he had exchanged messages.
The scandal began more than a week ago when a conservative website reported that a photo of a man's crotch had been sent from Weiner's Twitter account to a college student in Seattle.
For days, Weiner claimed that he hadn't sent the photo and that he was the victim of a hacker. But he caused guffaws when he said that he couldn't say with "certitude" that the underwear shot was not a picture of him.
The scandal escalated Monday when the website, BigGovernment.com, run by conservative activist Andrew Breitbart, posted photos purportedly from a second woman who said she received shirtless shots of the congressman. The site said the pictures were in a cache of intimate online photographs, chats and email exchanges the woman claimed to have. The website did not identify the woman.
One photo showed Weiner on a couch with two cats nearby. The website said Weiner sent the photo using the anthonyweiner(at)aol.com account with the subject line "Me and the pussys."
Also, the celebrity website RadarOnline.com said a woman claimed to have 200 sexually explicit messages from Weiner through a Facebook account that Weiner no longer uses. It was not clear whether the woman who claimed to have the new photo was the person who claimed to have received the text messages.
At Monday's news conference, Weiner said he sent the underpants photo as a joke and called it a "hugely regrettable mistake."
"I haven't told the truth and have done things I deeply regret," he said. "I brought pain to people I care about."
Genette Cordova, 21, the intended recipient of the crotch photograph, is a college student in Washington state. Weiner said he and Cordova had exchanged a few messages before he sent the photo May 27, which he said was intended to be "a joke."
In a strange twist, Breitbart attended Weiner's news conference and spoke to reporters before Weiner appeared. He claimed to have another photo of Weiner which he described as "X-rated" but would not say if he planned to release it.
"I would like an apology from him. I'm here for some vindication," Breitbart said. Weiner did apologize to Breitbart.
Weiner said he used his home computer and personal Blackberry, not government computers, in his exchanges with the women. But that may not protect him from House rules that say a member "shall conduct himself at all times in a manner that shall reflect creditably on the House."
On numerous occasions, the House ethics committee has cited that general rule in finding that lawmaker violated standards of conduct.
In her brief statement, Pelosi said she was "deeply disappointed and saddened about this situation." She mentioned Weiner's wife, his family, staff and constituents, but pointedly did not mention the congressman.
New York's senior senator, Chuck Schumer, said in a statement that he was "deeply pained and saddened by today's news. By fully explaining himself, apologizing to all he hurt and taking full responsibility for his wrongful actions, Anthony did the right thing. He remains a talented and committed public servant, and I pray he and his family can get through these difficult times."
Weiner succeeded Schumer in the House district that includes parts of Brooklyn and Queens.
The picture showing Weiner shirtless was reminiscent of a photo of former Rep. Chris Lee, a New York Republican who abruptly resigned from office earlier this year after a shirtless photo he sent a woman on Craigslist became public. A Democrat, Kathy Hochul, was sworn in to replace Lee last week after winning a special election May 24.
Weiner gained a national profile during the debate over President Barack Obama's health care plan when he outspokenly professed support for a government-run "single-payer" program for everyone and later a "public option" to compete with private health insurance. He got the notice of liberals even though both proposals failed to make it into law.
Associated Press writer Andrew Miga and Matthew Lee in Washington and Chris Hawley in New York contributed to this report.