POSTMORTEM: Josh Marshall has it about right, I think:

There will be a lot of talk about poorly executed tactics in various races. And there does seem to have been a late wave for Republicans — probably just enough to seal a number of contests, and quite likely related to the president’s election swing. But I think the issue here isn’t poor tactics so much as an over-emphasis on tactics in general. The Democrats have lots of long-term political and demographic trends in their favor. But they don’t really have a politics, a vision, or a message — or perhaps, better to say, the courage and imagination to get behind one. And I suspect that that is the underlying issue.

Tactics can make a difference, and they’re easy to focus on because they’re discrete and — in the warfare mode — they’re fun. But they’re supposed to be an adjunct to the message, not a substitute for the message. When you let them take over, you look like you don’t have a message, and like you’ll do anything to win. That was the import of the Wellstone funeral-cum-rally, and of a lot of other things that the Democrats have done, and it hurt them.

The Democrats need to fix themselves. Marshall predicts that a lot of heads will roll, and they should.