It's the reason the "down-low"-brothers-as-vectors-of-HIV myth received such credulous treatment in the mainstream media, as if "the closet" were an invention as black as jazz and as if health officials hadn't debunked the whole theory anyway.

It's why, when a prominent black pastor denounces gay marriage, it's taken as some sort of neat shorthand about the broader attitudes of his race in a way that a random white evangelical leader's similar proclamation would not. Our homophobia is more potent and obdurate, this premise goes, and not just a mundane old ugliness.

The less-sexy story here is that there's virtually no evidence that any prominent black leaders who have backed same-sex marriage -- Mayor Cory Booker of Newark, N.J., Gov. Deval Patrick of Massachusetts, Rep. John Lewis of Georgia, California Attorney General Kamala Harris -- have faced any measurable backlash from black voters for doing so. And black folks' support for gay marriage has grown more robust, just as attitudes on gay marriage have in every other demographic group. A Wall Street Journal-NBC poll (pdf) from March found that black support for gay marriage had jumped way up since October 2009, from 32 percent to 50 percent.

Then Obama made his announcement, and the needle really started to move: A survey of black North Carolinians found a 19-point swing in support of same-sex marriage after the president's statement; a majority of blacks now favor it there. Black support for same-sex marriage surged in Ohio and in Pennsylvania. In Maryland, where the aforementioned McCoy is trying to block gay marriage, a poll containing an oversample of black people found a solid majority now in support of legalizing it. And the Washington Post also found an 18-point swing in support among blacks across the country, although the paper noted that its black sample size was tiny.

Professional opinion havers spent the summer worrying that Obama's stance on gay marriage would hurt him among blacks, when the reality is that something much different was happening: Obama's stance apparently ended up bolstering African-American support for gay marriage. As support for marriage equality becomes enshrined as a mainstream Democratic position, black folks, who are overwhelmingly Democrats, are going to take that stance.

This isn't the neat and easy controversy that talking heads want, and it doesn't drive page views. Still, the next time this story pops up -- and it almost certainly will before November -- we should ask folks to show us the receipts.

Gene Demby is a Brooklyn, N.Y.-based writer and the founder of the politics-and-culture blog PostBourgie. Follow him on Twitter. 

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