The New Yorker has an interesting article on how voters vote: The Unpolitical Animal.
Some of the theories about what motivates (if anything) individuals to vote for whom is quite scary. The most striking idea discussed is that only about 10% of the electorate actually have anything close to a coherent political philosophy. And about 20% hardly have what one could call political views and make their voting decisions on gut.
The article also discusses how many voters have little understanding of the views they do hold--that they don't see how some views like being in favor of lower taxes excludes other views like increased social services or that when the polling question is rephrased the answer given is often in contradiction with the previous answer.
Roger is right!