Silly sausage Anthony Weiner pauses to reflect on the campaign trail. Anthony Weiner arrived at a fast clip, stalking down West 43rd Street with the grim determination of a man caught in a downpour without an umbrella. Other candidates for mayor of New York were expected to show, but the welcome outside the Martin Luther King Labour Centre was exclusively for him. He held his head up, focused on the building's mosaic mural, breathed in its Frederick Douglass quote - "if there is no struggle, there can be no progress" - and pushed his way through the crowd of microphones without saying a word. Inside the auditorium, there were more camera crews than there were members of the Democratic Party eager to hear Weiner's views about improving city services, but he held forth anyway, about sheltered housing and wheelchair-accessible taxis, always using the simple future tense, never the conditional: "That's gonna change when I'm mayor." By now, it is clear to everyone but Weiner that he is running a zombie campaign. As he lurches along, unsure what to do but run, his candidacy has become an experiment in what voters will and will not tolerate. How many New Yorkers will cast a ballot for a man who sends pictures of his erect penis to young women? How much more damaging does this behaviour become when he lies about it, confesses, then does it again? On Tuesday, Weiner released a defiant video - "Quit isn't the way we roll in New York City" - in response to calls for him to drop out of the race. Nancy Pelosi, the senior Democrat in the House of Representatives, said Weiner should do his therapy in private. David Axelrod, Barack Obama's former adviser, told NBC News: "It's time for him to go away and let New York have its mayor's race." In the latest Quinnipiac University poll, 53 per cent of likely voters agreed. Only 16 per cent said they intended to vote for him. The New York Post and The Daily News have been mocking Weiner on the front page almost every day since his admission that he continued sexting long after resigning from Congress two years ago. This week he also made the cover of The New Yorker: an illustration depicted him straddling the Empire State Building - King Kong style - merrily sexting. The New York Times and Wall Street Journal have called on him to withdraw from the race. The Times editorial was remarkably tart, coming from a newspaper that endorsed Bill Clinton for president twice, despite allegations of serious sexual misconduct against him. "Mr Weiner says he is staying in the mayoral race," it read. To those who know his arrogance and have grown tired of the tawdry saga he has dragged the city into, this is not surprising. Anthony Weiner. Newspapers routinely endorse and editorialise against political campaigns, but for all four dailies to state that a candidate should not be running is unprecedented, begging the question of what Weiner has done to offend so many powerful people. He has not been exposed as a hypocrite, like former New York governor Eliot Spitzer, who cracked down on prostitution and got caught using an escort service, or Idaho senator Larry Craig, who sponsored anti-gay legislation and was then arrested for soliciting sex in an airport toilet. He did not father an illegitimate child while cheating on his dying wife, like former senator John Edwards, nor abuse the power of his office like senator John Ensign, who attempted to cover up an affair with a staff member by getting her husband a job. He also did not ejaculate on a White House intern, encourage a mistress to lie to investigators or settle a sexual harassment lawsuit for $850,000 rather than go to court: in comparison with president Clinton, Weiner is like a schoolboy suggesting "you show me yours, I'll show you mine" in a shady corner of the playground. His main offence has been to sin, confess, then repeat the sin. "The American public is a rather forgiving one," says Alison Dagnes, author of Sex Scandals in American Politics. What we can't do is keep forgiving the same mistake over and over again. It insults our intelligence. In 2011, Weiner mistakenly uploaded a picture of his grey boxer briefs to Twitter in which his excitement was clearly visible, straining against the cotton. His first impulse was to claim that his Facebook and Twitter accounts had been hacked. "This is a prank - not a terribly creative one - and it's a distraction," he told CNN. Anchor Wolf Blitzer asked if he recognised the underpants. "It certainly doesn't look familiar to me," he replied. When the photograph's intended recipient, student Gennette Cordova, said it was not the first candid shot he had sent her, other women came forward with proof of the congressman's online activities. In messages to porn star Ginger Lee, he repeatedly referred to his "package." He fantasised about having sex with Las Vegas casino worker Lisa Weiss and watching television at the same time. Meagan Broussard said she had phone sex with him on a line from his Washington office. This set the stage for a rambling, tearful press conference that many believed would end Weiner's career. His name, a euphemism for the thing he was so keen to show to virtual strangers, is a gift to headline writers: "Weiner's Pickle," "Democrats let Weiner Shrivel," and so on. He shut down his Facebook account, with its 45,000 friends, stepped back from cable news appearances and began plotting his return. His decision to run for mayor less than two years later said much about the weakness of the field of Democrats vying to succeed Michael Bloomberg. Neither city council speaker Christine Quinn, nor former comptroller Bill Thompson, nor Public Advocate Bill de Blasio has Weiner's national profile or fund-raising ability. Weiner's wife, Huma Abedin, is Hillary Clinton's chief of staff. The comeback lasted two months before Weiner owned up to conducting more inappropriate online relationships under the pseudonym Carlos Danger. This time Abedin was at his side. "Anthony's made some horrible mistakes, both before he resigned from Congress and after," she said. We discussed all of this before Anthony decided to run for mayor, so really what I want to say is I love him, I have forgiven him, I believe in him. For some Democrats, this public humiliation of his wife was the last straw. To others, it was the sheer idiocy of handing his enemies a knife to stab him with. Campaign manager Danny Kedem resigned. As the tabloids ran interviews with Weiner's new paramours - he would be "too busy jacking off" to run New York, suggested one of his sext partners - it became clear that he had few friends left. On Wednesday, the saga took yet another twist when his communications director, Barbara Morgan, was forced to apologise after describing as a "slutbag" a young female intern who had alleged that many of those working on Weiner's campaign were doing so chiefly in the hope of getting a job with Hillary Clinton. "I don't think anybody feels fondly towards Anthony Weiner," says Dagnes. If you look at any of the other politicians in America who have been caught in sex scandals, there's always a constituent or two that comes forward to say 'look, the guy may have messed up but he helped save our neighbourhood'. No one has come forward to say Weiner's a good guy. In 12 years, he sponsored just one bill in the House of Representatives. Friends of the Clintons have been briefing against Weiner anonymously, alarmed that the scandal is a little too close to Hillary and a little too reminiscent of Bill's philandering. "Bill Clinton was the greatest political and policy mind of a generation," one Democratic insider told The New York Times columnist Maureen Dowd. Anthony is behaving similarly without the chops or resume. It is tempting to wonder if things might have turned out differently if Clinton had owned a smartphone when he was governor of Arkansas. Perhaps he would have sent Paula Jones a picture, rather than summoning her to his hotel room and exposing himself, as she alleged in her sexual harassment suit. "As Mr Weiner knows well, technology and social media have really aided the guys who are predisposed to this kind of offence, and that creates an evidence trail," says Professor Michael Miller, from the University of Illinois, who has studied the impact of political scandals on voting. Can you imagine Kennedy on Twitter? Miller's research showed that financial scandals are more damaging to politicians than moral scandals. Infidelity rarely kills a career. "If all you do is cheat on your wife, voters will forgive that," he says. But the repeated allegations make Weiner seem like a serial offender and what voters will not tolerate is someone who doesn't learn his lesson. Right now he's seen as a man who can't control himself, and that's not going to be good when it comes time for the voters to evaluate him. Few of the greatest presidents of the modern era have been faithful to their wives. Franklin Roosevelt had a long-standing affair with Eleanor's social secretary, Lucy Mercer. Dwight Eisenhower reportedly carried on with his driver, Kay Summersby. Lyndon Johnson is rumoured to have fathered an illegitimate son and was known in Congress for flashing his penis in the bathroom and boasting about its size. John F. Kennedy had one-night stands too numerous to count. These indiscretions were not widely reported at the time, but the history of political sex scandals in the US suggests that they may not have been especially damaging, even if they had been revealed. Two recent examples show how willing voters are to grant libidinous politicians a shot at redemption. In May, Mark Sanford, the former governor of South Carolina, was elected to serve the state's first congressional district, four years after telling his staff that he would be hiking on the Appalachian Trail and instead flying to Argentina to spend a fortnight with his lover. After serving out his term as governor and divorcing his wife, Sanford married his mistress, Maria Belen Chapur, and asked voters for a second chance. Louisiana senator David Vitter, a family values Republican, survived the 2007 revelation that he was a client of a Washington DC brothel, winning re-election three years later. "He kept his head down, you never heard from him, ever, about social issues," Dagnes says. His wife stayed with him. Their one press conference together said, 'This is between me, my wife and my pastor. I'm really sorry, I messed up and we're gonna go pray on it.'  In France, former managing director of the International Monetary Fund Dominique Strauss-Khan faces charges of "aggravated procurement" for his alleged role in a prostitution ring that hosted sex parties. "I long thought that I could lead my life as I wanted," he told French magazine Le Point. Although this is a long way from the "let he who is without sin cast the first stone" approach of politicians from the Bible belt, it is unlikely he would be prosecuted any more zealously in the US. On November 5, New York's voters will choose a city comptroller as well as a mayor. The leading candidate for this powerful position is Spitzer, the former governor once talked about as a presidential contender, before his fondness for high-class hookers was exposed by an FBI investigation. On MSNBC, Spitzer was asked whether he would cast a vote for Weiner as mayor. He said no. The next day's New York Post headline read: "Pot, meet Kettle." When he had finished speaking at the Labour Centre, Weiner hung around for a couple of minutes talking to party officials. A woman sitting behind me introduced herself as Robin Sherman-Epstein. "He was my congressman for many years," she told me. I know him. The trouble is now everyone else knows him too. Weiner started for the door, pursued by the press pack, the muscles in his neck bulging even more than usual, deep furrows across his forehead. Get roller skates. You'll need them," offered my new friend as I stood to leave. She was right. By the time I had hustled down the stairs to the street, he was gone. Andrew Purcell is a New York-based journalist.