There is an interesting theory by historians about this sort of topic. I'm not a student currently, so I can't post the sources (no access to the database). However, it goes like this:
Economy is bad --> Current President = Politician
--> "Country" wants = Businessman for next election cycle
Economy is bad --> Current President = Businessman
--> "Country" wants = Politician for next election cycle
I know, I'm really doing the theory no justice. If I can find my thumbdrive from that semester, I have like a 20 page essay on this theory. It makes for an awful read. I love history and I hated this paper.
The best example is when FDR beat out Herbert Hoover in 1932. The economy was so bad, and Hoover was a "businessman" and FDR wasn't. Hoover had been the Commerce Secretary, most notably. And obviously, FDR was not a businessman. If you can find any of the stuff on google about this theory, please post. I hope you can understand why I refuse to look it up right now
People generally don't understand the issues that the President has to deal with. It pretty much is a classic case of the President getting "too much blame when something goes wrong and too much praise when it goes well". Most people prefer to have the
opposite of who is already in charge if a change is going to take place. Not just with fiscal issues but, war. I guess those are the two biggest issues.
So, as a "no-longer-pursuing-history-degree-but-still-loves-the-subject" expert, I'd honestly have to say that the elections are more just people not being able to understand the issue for what it is and equate electing the opposite views/experience/etc. person as the best candidate for change. It happened with Obama in 2008 (ending the wars, Gitmo, healthcare etc.). He campaigned hard and in the opposite of what the conservatives stood for.
Rarely is a power-change in the US Government because of a certain ideology being preferred by the American people. It usually is a repercussion against the party currently in power.
I know many of you probably know and understand this concept. I feel that it's one of those things that applies to many topics, including this one.