Yet if the culture is moving on, national politics is not, or at least not as rapidly. Mr. Obama has yet to fulfill a campaign promise to repeal the policy barring openly gay people from serving in the military. The prospects that Congress will ever send him a bill overturning the Defense of Marriage Act, which defines marriage as between a man and a woman, appear dim. An effort to extend hate-crime legislation to include gay victims has produced a bitter backlash in some quarters: Senator Jim DeMint, Republican of South Carolina, sent a letter to clerics in his state arguing that it would be destructive to "faith, families and freedom."

"America is changing more quickly than the government," said Linda Ketner, a gay Democrat from South Carolina who came within four percentage points of winning a Congressional seat in November. "They are lagging behind the crowd. But if I remember my poli sci from college, isn't that the way it always works?"