Continuing my stand against 'junk research' here is a recent article from Wharton on the perils and pitfalls of polls.
As the author concludes:
The thing to think about with polls is the confirmation bias, which is basically that we are always looking for more evidence for the things we already believe in. If you are told as a child that 'elves cause rain, then every time it rains there is more evidence of elves.' We all end up with some set of opinions, but once we have them, we look for more evidence to reinforce them.