Robin Hanson recently wrote a relevant article on our sister site Overcoming Bias. I must insist that anyone who wants to comment it to read the whole thing and be familiar with the material he cites and links to, but for those who are just seeking a low cost conclusions from a vetted rationalists like him, the last paragraph summary:

So, as a professor of economics who has studied politics, my advice is to not vote if you know an average amount or less, to copy a better informed close associate if you are willing to appear submissive, and otherwise to just reelect incumbents when your life goes better than you expected. And if you care a lot more about the outcome than most do, help create presidential decision markets, so other info-seekers will have a better place to turn.