It is possible that the public loves the Olympics because it helps them forget politics. During the Fall, things heat up. The political advertising blitz begins in earnest. By October, the most jaded citizen develops some kind of interest in the race. In the weeks prior to the general election political polls take on an unusual importance.
Many voters have little party loyalty.
Many voters also want to support the winner. If the polls show that one candidate has a significant advantage over the other, the perception grows that the winner has already been chosen. Might as well go bowling instead of bothering to vote. If the race is close enough, the head to head television debates that will inevitably take place can be very important. Debates are the one facet of American presidential politics that almost everybody gets a kick out of.