It's not "we don't condone weird behavior".   It's, among other things, self-defense. The Democrats need to be concerned about what the Republicans would have done with this, had Weiner stayed.    They would have implied pedophilia, among other things--since Weiner really had no knowledge of the age of all the recipients of his "tweets".

And as I have already noted, what Vitter did has no bearing--that was a different regime. Under Boehner the GOP has had a policy of zero tolerance of this stuff.   See Chris Lee.

Also, Vitter did it with a prostitute.    Weiner's contacts were at least partly with high school and college girls.   And for some reason, though there was no actual sex involved, the fact that most of his contacts were not in the "sex trade" seems to make it seamier.

He did not help his cause by his general brash and aggressive attitude.   He had very few friends in Congress even before this--so the only one who even had any inclination to defend him was his former mentor, Chuck Shumer. Of course his lying about it probably alienated more people than anything else.

The Democrats were also just livid about the timing--up to now they had the GOP on the defensive about the Ryan plan for overhaul of Medicare, and they were making great headway in branding the GOP as against old people. They did not welcome any kind of diversion from this campaign--especially something of this nature.

On top of all this, as I noted earlier, is the Democrats' need to appeal to women.   At this point the gender gap with women favors the Democrats.    They cannot afford a loss of this.

And it is amazing how some women feel about it.   I told earlier about the 21-year old who was bitterly disappointed in Weiner.   That's nothing compared to Jan, who is as liberal (radical, even) as they come.   At this point she loathes and despises Weiner, and has told me his wife should divorce him immediately, since otherwise the father's conduct will follow their child his or her whole life. I thought it was more important that her child have his or her own real father--but that's just my view.

One other question:   I've read Weiner still has a $4 million campaign fund.   What happens to it now?