With a full week of polling data from after the two conventions, we are starting to get a better sense of the size of the convention bounces. But what do those bounces tell us about likely winner come November? Using a variety of sources,we can estimate a few facts about convention bounces and eventual election outcomes:
- Looking at the 12 Presidential elections beginning with 1964, we see that the ultimate winner has gotten the larger post-convention bounce in six elections and the smaller post-convention bounce in six elections. Not much predictive power there. (The party out of power has gotten the larger bounce in seven elections and the smaller bounce in five.)
- It is rare but not unheard of for candidates to out-perform their post-convention peak. Among the 22 major-party Presidential candidates running since 1968, there appear to be three cases where candidates out-performed their post-convention polling numbers: Hubert Humphrey in 1968, Gerald Ford in 1976, and George H. W. Bush in 1998. All three were incumbent-party candidates, although Bob Dole appears to have performed about as well as his post-convention peak in 1996, too.
