I am beginning to think the Dems are no longer getting a bounce from their conventions because it is just a repeat of the major news outlets. It has turned into essentially a re-run of the nightly news. When the people then turn their attention to the GOP convention they hear the message unfiltered straight from the candidates - without interpretation or soundbites from Katie Couric or the AP - and shift their support to the GOP canddidates.
kerry did get a bounce coming out of his convention- 4-to-5 pts in most polls..
http://www.realclearpolitics.com/bush_vs_kerry_hth.html
The Bush campaign was building up a lot of momentum after the conventions, and I believe they were headed for a comfortable victory. Then the race tightened back up after Bush stumbled through the last half of the first debate.