efore Obama endorsed gay marriage, many of its opponents were confident that they could repeal Maryland’s new same sex marriage law by holding a referendum on the issue. Now, they can’t be so cocky. A poll released yesterday shows that Maryland’s support for gay marriage has increased 12 percent since Obama’s endorsement, with most of the shift coming from African-American voters who have flipped their stance on the issue. Fifty-five percent of Maryland blacks now support gay marriage and would vote against such an amendment and 36 percent oppose it, according to the poll. It’s likely Obama’s endorsement affected them. Before it, 56 percent of blacks opposed gay marriage and 39 percent supported it. Below are the full poll results. Check out how participants answered the individual questions.