Neither candidate got much of one. The Moderate Voice explains:
A new Gallup Daily tracking poll taken after the Democratic convention and after Republican Senator John McCain picked Gov. Sarah Palin as his running mate shows Democratic Presidential nominee Sen. Barack Obama’s lead down two points. Obama now has a 6 point lead.
Both Gallup and a website that analyzes polls suggest this means (1) Obama didn’t get much of a convention bounce but its hard to judge given the rapidity of McCain’s Veep announcement, (2)McCain’s Palin pick didn’t give him an out of the ordinary Vice Presidential pick bounce, and (3) if the Palin pick is factored in Democrats shouldn’t be too upset because Obama seemingly held up fairly well.