The ex-congressman whose career imploded in a rash of raunchy tweets two years ago said in a YouTube video announcement late Tuesday that he's in the New York City mayoral race. He'd said last month he was considering it.
"I made some big mistakes and I know I let a lot of people down, but I also learned some tough lessons," he said in the video. "I'm running for mayor because I've been fighting for the middle class and those struggling to make it my entire life. And I hope I get a second chance."
With that, Weiner is embarking on an audacious comeback quest, hoping to go from punch line pol whose tweeted crotch shot was emblazoned on the nation's consciousness to leader of America's biggest city.
The video appeared late Tuesday, then disappeared for a few hours but was back online by 5 a.m. Wednesday. A call to Weiner was not immediately returned Wednesday.
A Quinnipiac University poll, conducted May 14-20 and released Wednesday, places Weiner second in the pack for the Democratic nomination. City Council Speaker Christine Quinn has 25 percent, followed by Weiner, with 15 percent.
The Democrat is jumping into a crowded field for September's primary. He's arriving with some significant advantages, including a $4.8 million campaign war chest, the possibility of more than $1 million more in public matching money, polls showing him ahead of all but one other Democrat - and no end of name recognition.
His participation makes a runoff more likely, and many political observers feel he could at least get to the second round.
But Weiner also has continued to contend with questions about his character and the scandal that sank his career just two years ago.
After a photo of a man's bulging, underwear-clad groin appeared on his Twitter account in 2011, he initially claimed his account had been hacked. After more photos emerged - including one of him bare-chested in his congressional office - the married congressman eventually owned up to exchanging racy messages with several women, saying he'd never met any of them. He soon resigned.
In recent interviews, he has said he shouldn't have lied but did it because he wanted to keep the truth from his then-pregnant wife, Huma Abedin, a longtime aide to former Secretary of State Hillary Rodham Clinton. She told The New York Times Magazine that she has forgiven him.
Weiner has taken a series of steps recently to rehab his image and reintroduce himself, including the lengthy magazine profile and a series of local TV interviews. He hasn't responded to interview requests from The Associated Press.
He also has released a platform of sorts, a list of ideas styled as a blueprint for helping the city's middle class thrive. He's made a point of highlighting one or more of the concepts on most days, via his newly revived Twitter presence.
The suggestions, some of them updates from a mayoral run he nearly made in 2009, range from giving every public school student a Kindle reader to using Medicaid money to create a city-run, single-payer health system for the uninsured.
Some seem to draw on his Washington experience, such as making more use of a federal cigarette-smuggling law. But others fall squarely within City Hall, including suggestions to create a "nonprofit czar" in city government and eliminate paid positions for parent coordinators in schools.
The document also opens a window on a vision of the city - a place with "a can-do attitude, competitive spirit and aggressive nature" - that sounds not unlike Weiner himself. He was known during his seven terms in Washington as a vigorous defender of Democratic viewpoints, unafraid to get combative whether it was on cable TV or the House floor, and as a tireless and instinctive politician.
"Anybody who underestimates Anthony Weiner's ambition is a fool. And anybody who underestimates his ability as a candidate is a fool," retired Hunter College political science professor Kenneth Sherrill said. But "we're going to see, basically, if Weiner can take hits as well as he can dish them out."
In seeking a second chance from the public, Weiner will have to overcome some voters' misgivings. In a recent NBC New York-Marist Poll, half said they wouldn't even consider him, though the survey also showed that more registered Democrats now have a favorable than unfavorable impression of him.
Weiner can expect opponents to hammer at his prior prevaricating, and he said in a recent interview on the RNN cable network that he couldn't guarantee that no more pictures or people would emerge.
And while he might welcome attention to his policies rather than his past, they also have attracted some criticism. About a dozen young people recently demonstrated outside his Manhattan apartment building to denounce his proposal to make it easier to suspend disruptive public school students; "(hash)Weiner: You ask for a second chance in (hash)NYC2013 but deny students a second chance," read one sign, using Twitter's beloved hashtag marks.
Since leaving office, Weiner has put his government experience to work as a consultant for various companies.
His Democratic opponents include City Councilman Sal Albanese; Public Advocate Bill de Blasio; Comptroller John Liu; City Council Speaker Christine Quinn; the Rev. Erick Salgado, a pastor; and former Comptroller Bill Thompson.
Republican contenders include billionaire businessman John Catsimatidis, former Metropolitan Transportation Authority Chairman Joseph Lhota and homelessness-aid organization head George McDonald. Former White House housing official Aldolfo Carrion Jr., a Democrat who recently dropped his party affiliation, is running on the Independence Party line and also interested in the Republican nomination.