New York Rep. Anthony Weiner is fighting for his political life after admitting inappropriate conduct online with multiple women (REUTERS/Brendan McDermid )

Weiner was insistent in his mea culpa yesterday — a statement that included an admission that he had taken and sent a lewd photo to a college student in Seattle, Washington — that he had broken no laws and would not resign. “Nothing about this should reflect on my official duties or oath of office,”he said.

But, in the wake of his press conference there are a number of signs that suggest hanging on to his House seat will be tough.

“He is in a deep, dark, unspinnable place,” said Democratic crisis communications expert Chris Lehane.

There are three major hurdles for Weiner as he tries to weather this scandal and remain in Congress.

1. House Minority Leader Nancy Pelosi (Calif.) and Democratic Congressional Campaign Committee Chairman Steve Israel (N.Y.) both immediately called for the House ethics committee to look into whether Weiner broke any laws with his online conduct. That move was a not-so-subtle sign from two of the top leaders in the party that it might be time for Weiner to exit stage right. (Democratic leaders fumed behind the scenes last week as Weiner struggled to explain himself, insisting that his personal foibles were making it difficult to keep the focus on Republicans’ Medicare woes.) Republicans, sensing opportunity, are ramping up the pressure on Democrats in regards Weiner; Republican National Committee Chairman Reince Priebus said Tuesday morning that Weiner should resign.

2. Weiner acknowledged he had “inappropriate” online relationships with six different women. As of right now, we know the identities of only three of those women. Given the massive amount of media attention this story has attracted, it’s a near-certainty that the other women will either come forward or be pushed into the limelight over the next few days/weeks. Even if there are no more pictures — and Weiner acknowledged yesterday that there very well might be — every time some new detail emerges, it will give new life and a new angle to the story. That makes putting it behind him very, very difficult for Weiner. And, the longer he twists in the wind, the tougher it is for him to hang on.

3. Weiner exists in the most active and, well to be blunt, carnivorous media environment in the country. The New York City press corps are famous for their doggedness and love of a good political scandal. And, this is not a good political scandal but a great one. Judging from some of the questions at Weiner’s press conference yesterday — one woman just kept yelling “Did you have phone sex?” — it’s going to get worse before it gets better for Weiner. A number of questions remain unanswered and there’s almost no chance that the New York press corps will rest until Weiner provides some (more) answers.

With all that said, recent political sex scandals have shown that the need to resign is in the eye of the beholder.

Former New York Rep. Chris Lee (R) stepped aside within hours after a shirtless picture made its way online. Former New York Gov. Elliot Spitzer (D) held out for two days after revelations that he had frequented a prostitute but then stepped aside.

Louisiana Sen. David Vitter (R), on the other hand, not only didn’t resign after admitting his involvement in a prostitution ring but managed to easily win re-election in 2010.

The decision to resign then rests almost entirely with the politician — barring clear evidence that laws were broken (ala former Reps. Duke Cunningham or Jim Traficant ) in which your hand can be forced.

At the moment, Weiner has given no indication that he plans to rethink his pledge to stay in office. But, he also said on two occasions over the past seven days that he was done talking about his online conduct — and we know how that turned out.

Weiner has to hope that no more revelations come to light in the next few days and that something comes along in the political world that distracts everyone from his current problems.

That scenario seems unlikely right now. But, politics changes rapidly — the last week is evidence of that. Weiner needs the winds to shift — and fast.