Mike Tomasky looks at the numbers and sees the possibility of a brokered convention. As a corollary to my view that it's never a good time for a third-party presidential candidacy, I've decided that it's also never a good time to predict a brokered convention. I completely agree with Tomasky's logic, but similar logic applied in 2004, to some extent in 1992, to a large extent in 1988, etc., etc., etc. The rules of delegate-allocation strongly suggest that multicandidate races should end without anyone securing a majority. In practice, that's not how it works. People are muscled out of the race and nothing get brokered.
So, on the one hand, I think Tomasky's right. On the other hand, I'm pretty certain he's wrong. In the event of brokering, the easy case is that Edwards has more delegates than Obama, Edwards + Obama equals a majority, and so we get an Edwards-Obama ticket. I feel like it would be weird for Edwards to run for Vice President a second time if the delegate counts are flipped, but that could happen, too. If there's serious deadlockage, though, then Al Gore, older, wiser, and heavier, becomes president. Indeed, I'm eagerly awaiting paranoid conspiracy theories about Gore's efforts to manipulate the primary in order to cause a deadlock.