Just heard this on the radio and don't know how accurate it is, but thought it interesting.

Supposedly, the Obama victory is part of the reason that so many of those anti-gay marriage ballot measures passed. Obama's candidacy got out the vote, including the African American vote and, in general, African Americans tend to be opposed to gay marriage.

As a result, people who might have otherwise not showed up to vote against the gay marriage propositions came out in force.