

Gay marriage supporters and opponents demonstrate outside the Federal Appeals Court in Richmond, Va., last month. (AP Photo/Steve Helber)

Gay marriage supporters continue to win their battles -- almost without exception.

A big reason: Because gay marriage opponents don't have much interest in waging the war.

A new Washington Post-ABC News poll shows that 56 percent of Americans support the right of gay people to get married, and another 50 percent believe it's a constitutional right. That's pretty much in line with recent polling showing support for gay marriage on the rise.

And while gay marriage opponents are an ever-shrinking portion of the population, just as importantly, they are far less keen on pressing the issue.

The new poll also asked people how important the issue of gay marriage is to their vote for Congress. While 81 percent of strong gay marriage supporters say it's at least "somewhat" important, just 50 percent of strong opponents say the same.

Nearly half of those who strongly oppose gay marriage (48 percent) say it's not even somewhat important to them. Just 19 percent of strong gay marriage supporters are so casual about it.

If you project those numbers over all strong gay marriage supporters and opponents, the advantage for supporters is even clearer.

While 30 percent of Americans say they strongly oppose gay marriage, if only half of them think it's even somewhat important to their vote, you can deduce that only about 15 percent of Americans feel passionately enough about the issue that it has any impact on their vote.

By contrast, about twice as many Americans -- around 30 percent -- say they support gay marriage strongly and that it's at least somewhat important to their vote. Around 20 percent say it's at least "very" important.

In politics, motivation is hugely important. And gay marriage opponents don't have it right now.

Peyton M. Craighill contributed to this post.

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