(New York City) Proposed bans on same-sex marriage are on the ballot in three important states this fall, rousing passions on both sides, yet neither John McCain nor Barack Obama seem eager to push the issue high on their campaign agendas.

In California, the stakes are particularly high – it’s the first time a ban-gay-marriage amendment goes before voters in a state where same-sex couples already have the right to wed. Similar amendments are on the ballots in Florida, a battleground in the presidential race, and Arizona, McCain’s home state.

McCain supports the amendments, Obama opposes them – yet the two nominees rarely mention them proactively as they compete for middle-of-the-road voters who rank the marriage debate low on their list of concerns.

“It doesn’t benefit either one to promote it for their own campaign,” said Matthew Corrigan, a political science professor at the University of North Florida. “You have the economy, the war. It makes it more difficult for social issues to get people’s attention.”

Both presidential candidates say they oppose same-sex marriage, although Obama adds that his personal beliefs do not translate into support for banning it. And unlike McCain, Obama has declared his support for civil unions that grant marriage-like rights to gay and lesbian couples.

McCain, while asserting it’s an issue for states to decide, has endorsed the proposed bans on this year’s ballots and has not advocated for federal recognition of the various same-sex partnerships now legal in 10 states.

In the past, McCain has voted against a federal ban on same-sex marriages, but in this campaign he’s signaled he would back such a ban if federal judges sought to impose them on states that didn’t want them.

For partisans on both sides, there’s a degree of frustration that marriage isn’t more prominent in the campaign, coupled with an understanding that economic issues are taking precedence.

“We wish it were a top issue – it seems not to be,” said Tom Minnery, a senior vice president with the conservative Christian group Focus on the Family.

In Florida, where presidential campaigning will be intense, gay-rights activists hope Obama will not be too cautious in discussing the state’s ban-gay-marriage measure.

“We would like Sen. Obama to be much more emphatic in his opposition to Amendment 2. We’d like his campaign to acknowledge that in a stronger way,” said Stephen Gaskill, a spokesman for the Florida Democrat’s gay and lesbian caucus.

The spotlight on same-sex marriage will be brightest in California, where Proposition 8 would amend the state constitution to limit marriage to a man and a woman. If approved, it would overturn a California Supreme Court ruling that made the state only the second, after Massachusetts, to legalize same-sex marriage.

Statewide polls indicate the amendment will be defeated, but both sides are raising millions of dollars for a campaign they depict in epic terms. Opponents of same-sex marriage say California represents a last chance to block its spread; gay-rights activists say affirmation of it by voters in the largest state would be a watershed victory.

The president of the largest national gay-rights group, Joe Solmonese of the Human Rights Campaign, expressed hope that young voters – who are relatively supportive of same-sex marriage – will help defeat Amendment 8 while turning out in large numbers to back Obama.

Some conservatives see the possibility of a contrasting demographic trend in Florida, with churchgoing African-Americans turning out in huge numbers for Obama while casting votes for the ban-gay-marriage measure.

“We’re expecting black support,” said John Stemberger, who heads the campaign for the Florida amendment.

Florida is unusual among the states – requiring 60 percent support from voters for proposed constitutional amendments to be enacted.

“If the threshold were 50 percent, it would likely pass, but 60 percent is a very difficult scenario,” said David Johnson, former executive director of Florida’s Republican Party.

The Arizona campaign is noteworthy because in 2006 it became the only state to defeat a proposed ban on same-sex marriage. Similar measures have passed in 27 other states.

The Arizona measure failed two years ago in part because opponents contended it would jeopardize domestic partnerships and other arrangements benefiting unmarried couples. This year’s version has been streamlined to simply define marriage as between a man and woman; its prospects are considered strong.

Yet gay-rights activists insist that same-sex marriage and other “culture war” issues will be less effective for Republican candidates than in November 2004, when marriage amendments won approval in 11 states.

“No matter where you fall on the issue of marriage, people are seeing these divisive tactics for what they are,” Solmonese said

Solmonese said there is broad support for Obama among gays despite his hesitancy on same-sex marriage. In contrast to McCain, Obama supports other gay-rights priorities – extending job discrimination and hate-crimes laws to cover sexual orientation, and scrapping the “don’t ask, don’t tell” policy that bars gays from serving openly in the military.

John Marble of Stonewall Democrats, which represents the party’s gays and lesbians, said activists were encouraged that Obama was wrestling with how to extend federal recognition to same-sex couples.

“We’re not in total agreement with him, but at least he’s engaging in that conversation,” Marble said.

Marble and Solmonese said McCain was sending two sets of signals regarding same-sex couples – telling conservatives he firmly opposed gay marriage while suggesting to moderates that same-sex relationships were entitled to some sort of legal recognition. They said his choice of Alaska Gov. Sarah Palin as running mate reinforced his message to the religious right, which views her as a staunch opponent of same-sex marriage even though she hasn’t publicly raised the issue since her nomination.

“McCain has been quite skilled at wrapping up discriminatory views in a nice package,” Solmonese said. “I couldn’t tell you where his heart genuinely is.”