I chatted with quite some people. It looks like there are two camps of voters in the US. In one camp, their basic beliefs determine their votes. They are either democrats or republicans but they seldom sway. In the other camp, voters do not have strong basic beliefs, policies promised by the candidates often determine their votes. This camp sways.
I personally have two basic beliefs: 1. all governments waste; 2. Market works. In addition, I am pro choice. I do not trust politicians. One person I chatted with told me he is a strong believer that what makes America a great country is one is not who he is but what he does. He thus tends to be a republican, seeing democrats trying to much to change that.