Of the early potential Democratic contenders, Maryland Gov. Martin O’Malley says he supports gay marriage but stopped short of making a major push for the legislation earlier in the year, while Virginia Sen. Mark Warner is opposed. Hillary Clinton, if she runs, would still have her commitment to civil unions but not gay marriage from the 2008 race hanging over her — and at least until the end of next year, when she’s said she’ll be done at the State Department, she won’t be able to make any new comments on the issue. “It gives him an authenticity and a...