Like most political scientists, I have long believed that people decide how to vote depending on their views on different issues. Maybe we have that backwards. Maybe how people regularly vote strongly conditions how they view public policy.
Dana Milbank has some evidence pointing that way. He notes that huge majorities in both parties switched from feeling the country was "on the wrong track" depending on who was in the White House. In 2008, Democrats felt that way and Republicans didn't. Today, Republicans overwhelmingly say "wrong track" while few Democrats do. I guess the party preference shapes how people view the facts.