Barack Obama has so far received anywhere from a 5 to 8 point bounce from the Democratic National Convention (depending on when it’s measured from), and now leads John McCain 48 to 42 in the latest Gallup tracking poll.

Gallup notes:

Since I thought last night was the strongest, I would say that this is a solid but not overwhelming bounce for Obama. With McCain’s VP choice set to be formally announced tomorrow (though possibly leaked this evening) and the Republican National Convention starting up on Monday, any bounce is likely to be short-lived. Remember that Obama went up by 9 points initially when on his European trip, but that quickly evaporated as McCain unvieled a series of sharp attacks, including the celebrity ad. Really, we won’t see any meaningful polling until the week of Sept. 8, after Americans have digested both conventions. But it’s hard to look away.