Democrats Poised to Pass Health Bill, Fall on Their Swords

So it looks like it's going to pass. Megan McArdle predicts political suicide:

So there's now about a 90% chance that the health care bill will pass.

At this point, the thing is more than a little inexplicable. Democrats are on a political suicide mission; I'm not a particularly accurate prognosticator, but I think this makes it very likely that in 2010 they will [lose] several seats in the Senate--enough to make it damn hard to pass any more of their signature legislation--and will lose the house outright. In the case of the House, you can attribute it to the fact that the leadership has safe seats. But three out of four of the Democrats on the podium today are in serious danger of losing their seats.

No bill this large has ever before passed on a straight party-line vote, or even anything close to a straight party-line vote. No bill this unpopular has ever before passed on a straight party-line vote. We're in a new political world. I'm not sure I understand it.