Political statistician Nate Silver was way off when it came to predicting the marriage equality vote in Maine, and he responded to his predictions on his blog, FiveThirtyEight.com.

The 31-year-old Silver, who successfully predicted President Obama's win last year, estimated that there was a 70% chance that Maine's Question 1 would fail, i.e. only a 30% chance that gay marriage would be banned. Instead, the same-sex marriage ban was passed by 53% of voters, a slightly higher percentage than California's Proposition 8 won by in 2008.

"I don't know how much time I'm supposed to spend defending being on the wrong side of a 70:30 bet -- we build in a hedge for a reason -- but here comes a little self-reflection," Silver wrote. "As for the polling, I think we have to seriously consider whether there is some sort of a Bradley Effect in the polling on gay rights issues."

Silver was referencing Tom Bradley, Los Angeles's African-American mayor who, while showing strongly in the polls, ended up losing California's 1982 gubernatorial race. The resulting theory was that some people who won't admit in polls that they're against minority candidates or interests will exhibit prejudice within the anonymity of the voting booth.

Silver praised the No on 1 campaign, and wondered if maybe some people cannot be swayed on the issue of same-sex marriage.

"I certainly don't think the No on 1 campaign can be blamed," he wrote. "By every indication, they ran a tip-top operation whereas the Yes on 1 folks were amateurish. But this may not be an issue where the campaign itself matters very much: people have pretty strong feelings about the gay marriage issue and are not typically open to persuasion."