This milestone result caps a dramatic, long-term shift in public attitudes. From a low of 32 percent in a 2004 survey of registered voters, support for gay marriage has grown to 53 percent today. Forty-four percent are opposed, down 18 points from that 2004 survey.

The issue remains divisive; as many adults “strongly” oppose gay marriage as strongly support it, and opposition rises to more than 2-1 among Republicans and conservatives and 3-1 among evangelical white Protestants, a core conservative group. But opposition to gay marriage has weakened in these groups from its levels a few years ago, and support has grown sharply among others – notably, among Catholics, political moderates, people in their 30s and 40s and men.