I think Bush won because he didn't neglect the extremely conservative evangelical christians, who stayed home 4 years ago.
Add the lies about Kerry's vietnam era (swiftboat veterans or how was it named?) and the third world style elections in a lot of places, which scare away people who don't feel very passionate about any of the candidates.
I might be wrong, but I think there were more voters who would never vote for someone who is pro-choice or in favor for equal rights for gay people then there were people who truly hated Bush.