Will Obama's endorsement of gays undercut his support among Blacks?

Christian Science Monitors:

But in these two Southern swing states, some polling and anecdotal evidence is giving rise to Democratic concerns that African-American enthusiasm for President Obama has slipped as a result of stubborn economic despair, deteriorating inner city conditions, a sense among voters that Obama no longer needs the black vote to win, and disagreements over social issues, including the president’s embrace of same-sex marriage. Heightening those concerns is the recognition by campaign strategists and analysts that, to win reelection, Obama likely needs to get close to the 65 percent of black voters who turned out in 2008 to vote in 2012.