The results, based on Gallup's annual Values and Beliefs poll, are down slightly from 53 percent last year, but mark the second time in Gallup's history of tracking the same-sex marriage question that at least 50 percent of Americans support legal gay marriages. Forty-eight percent said same-sex marriages should not be legal.
The issue of same-sex marriage falls along political and religious lines. Nearly two-thirds of Democrats support legalizing it, compared with 57 percent of independents and 22 percent of Republicans, the Princeton, N.J., polling agency said.
Fifty-one percent of Catholics said same-sex marriages should be legal while 47 percent said they should not. Protestants were more divided, with 38 percent saying gay marriages should be legally recognized and 59 percent saying they should not be legal. Those who identify with no religion overwhelmingly approve, 88 percent to 12 percent.
Vice President Joe Biden said Sunday on NBC's "Meet the Press" he was "absolutely comfortable" with the idea that same-sex and heterosexual couples are "entitled to the same exact rights, all the civil rights, all the civil liberties."
Results are based on telephone interviews with 1,024 adults conducted May 3-6. The margin of error is 3 percentage points.