Watching The Polls

Joyner is about right:

My guess is that Obama will build a double digit lead over the next few weeks as Democrats coalesce around him but that his numbers will fluctuate dramatically based on events on the ground. McCain will almost certainly get a convention bounce late. Beyond that, Obama will make the inevitable gaffes candidates make during a long, grueling campaign and he’s more prone to embarrassing revelations than McCain simply because he’s less of a known commodity.