President Obama had some explaining to do after announcing his personal support for same-sex marriage last week. Not to voters or party leadership, but to the ministers he called two hours after his television appearance. “They were wrestling with their ability to get over his theological position,” said the Rev. Delman Coates, a Baptist pastor who was on the conference call with other religious leaders, including some who said that Obama’s choice may cost him their support. In Newsweek,Andrew Sullivan explores how the president’s biracial identity led him to his historic announcement, one that could tip America toward marriage equality for all.