http://www.alternet.org/election04/19463/The public responded well to John Kerry's speech at the Democratic convention – even if the press didn't say so.
There's been much discussion of the fact that John Kerry didn't receive a significant "bounce" in the polls coming out of his convention. The consensus explanation is that since most people have already made up their minds, Kerry didn't have many people to persuade. Much of the traditional convention bounce comes from voters in the nominee's own party who finally get an extended look at him and in effect "come home" to where they're going to wind up eventually anyway. Since nearly all Democrats have already decided they're voting for Kerry (approaching 90%), and he already leads Bush among Independents by a substantial margin, there just wasn't anywhere to bounce to.
Nonetheless, most polls showed some modest gains. The ABC News/Washington Post poll, Newsweek poll, and CBS News/New York Times poll all showed Kerry picking up a few points, between 2 and 8.
The exception was the Gallup poll, which actually showed Bush gaining a few points on Kerry coming out of the Democratic convention. But here's a basic fact about survey sampling: Every survey is an extrapolation from a small number of people to a larger population; sometimes you're right, and sometimes you're off, even if your methodology is perfect. When four polls are taken at the same time, and three show the same results but one has something completely different, it's the lone outlier that's probably mistaken.
Interesting analysis of the polls demonstrating the double digit jump Kerry got in most instances in issues where he was poorly defined prior to the convention[/i/