History shows us that after eight years of rule by one party or the other, the electorate is generally pretty bored and dissatisfied, regardless of the performance of the incumbent, and leans towards a change. It thus behooves the party out of power to pick someone who is as inoffensive as possible in order to take advantage of the odds.
2000 is a good example. While it may seem quaint now, George W. Bush ran as a “compassionate conservative” with a “humble” foreign policy. Never mind what we actually got; this was a message that had plenty of appeal to the center.
In 2016, the GOP is set to nominate Donald Trump. So much for learning the lessons of history.
Hey, nobody said these guys were smart.