It looks like Barack Obama may have gotten his convention bounce after all:
A large number of national polls have come out within the past 24-48 hours, most of which had conducted a survey close enough to the beginning of the Democratic convention to provide for a direct comparison. These polls show Obama having gained between 2 and 8 points since before the convention began, or an average of 4.4 points. Although this is slightly below the average convention bounce of 6 points, it is a pretty reasonable result considering that the Republicans had named their VP candidate immediately following the Democratic convention, a circumstance which had never occurred before. Moreover, the internals of these polls show Obama gaining ground among Clinton supporters, a group of votes that John McCain is likely to have a difficult time getting back.
(Note: I have not included the Zogby Interactive poll in the table above -- this was the same poll that had Obama winning Arizona, and winning North Carolina by 8 points. But it is "officially" included for purposes of our model).
Still, it is imperative for Democrats not to get too giddy. A bounce is usually just a bounce, and the Republicans will have three nights of rebuttal tonight through Thursday to attempt to generate some momentum of their own. The Republicans rallied the base with the selection of Sarah Palin; having done so, they need to find messaging during their convention that will appeal to moderates and independents.