Thirty-eight percent of Americans support same-sex marriage and 24 percent support civil unions, while 33 percent oppose both, according to a new CBS News/New York Times survey. Only 32 percent of those surveyed think the federal government should determine whether same-sex marriage is legal, and 57 percent favor letting individual states make that decision. Yet 50 percent favor an amendment to the U.S. Constitution banning same-sex marriage. Sixty-seven percent of those surveyed think President Obama is now supporting gay marriage "mostly for political reasons," though 57 percent said his decision would have no effect on which candidate they support. A Washington Post/ABC News poll found voters nearly evenly split on Obama's announcement, with 46 percent having a favorable view and 47 percent unfavorable.