WHY HILLARY FIGHTS….John Heilemann’s piece in New York magazine about how Barack Obama blew his chances of getting an endorsement from John Edwards is fascinating reading. So go read it. But I was also intrigued by this:

Democrats are right to fear that [Hillary] Clinton may find it irresistible to turn her campaign into an exercise in nothing less (and little more) than political manslaughter against Obama. They’re especially right to be worried that she may want to fight on all summer, all the way to the Denver convention — especially with Clinton now talking openly about a floor fight over seating the disputed Florida and Michigan delegations.

Some senior members of Clinton’s campaign have no intention of sticking around if Obama is substantially ahead come June; as much as they’re devoted to their boss, they want nothing to do with a black-bag operation designed to destroy her rival, no matter what the cost. But these same people are also deeply convinced — beyond spin, beyond talking points, to their core — that Obama would be doomed against McCain. And Clinton believes this, too, which is one important reason why she persists despite odds that grow longer each passing day.

A couple of weeks ago I would have written this off as delusional. Of course Barack Obama can win against John McCain. And I still believe that.

But I’d be lying if I didn’t admit that the Jeremiah Wright controversy has shaken my confidence a bit. This has nothing to do with the substance of the thing, which I think has been wildly overblown, but by the conservative reaction to it. Go scan The Corner and you’ll find Mark Steyn and Victor Davis Hanson and the rest of the gang still in an absolute lather over Wright. Ditto for other conservative sites. They have no intention of allowing this to die, and I have no doubt that it will resurface with a vengeance in every last swing state this fall. When Obama continues to fail to denounce Wright thoroughly enough — and believe me, no denunciation will ever be enough with this crowd — then eventually the crossover Republicans who were singing Obama’s praises after Super Tuesday will, sadly but inevitably, use this as an excuse to switch their support to McCain. Can’t vote for a guy who doesn’t have the balls to disown an outraged black guy in a dashiki, after all. Ditto for a lot of political moderates who have fallen under the Obama spell but are really more anti-Hillary than they ever were pro-Obama.

Now, my guess is that, in the end, this won’t work. The polls taken after Obama’s race speech showed, gratifyingly, no reduction in his support, suggesting that a sleaze campaign will have a harder time working against Obama than it did against John Kerry. Still, it’s out there, and it’s pretty clearly part of the game plan for the fall campaign. I think Hillary’s folks are wrong to believe that Obama is doomed, but I’m not sure I think they’re delusional any more. There’s every sign that we have an ugly campaign ahead of us.