Backers of an initiative to repeal Proposition 8, the California ban on same-sex marriage, have failed to gather enough signatures to place it on the ballot in November.

The supporters say they will try to qualify the measure for the November 2012 election.

Gay rights activists had been split on whether to push such a measure this year or in 2012. The largest groups supported waiting for the next presidential election. Those supporting a vote this year said the division hampered their fundraising and volunteer efforts.

They needed slightly more than 694,000 signatures of registered voters to place the measure on the ballot and had until Monday to collect that amount. Leaders of the effort would not disclose how many signatures they gathered.

"It wasn't close enough to submit signatures to county registrars," said Sean Bohac, who was chairman of an advisory panel for the effort, called Restore Equality 2010. The group raised about $10,550, according to the California secretary of state.

Prop. 8 supporters said the failure shows that voters in California prefer allowing only heterosexual couples to marry.

"Even the minority of Californians who voted against Prop. 8 have accepted that the majority rules and moved on to other issues," said Brian Brown, executive director of the National Organization for Marriage, a major backer of Prop. 8.

Prop. 8 passed in November 2008 with 52 percent of the vote. Opponents have filed a federal lawsuit over the ban, which could end up before the U.S. Supreme Court. A poll conducted by the Public Policy Institute of California last month found for the first time more voters support same-sex marriage than oppose it, with 50 percent in favor and 45 percent in opposition.

Bohac said that he expects gay rights groups to unify behind the effort to repeal the ban in the 2012 election and that he does not expect the rift to have damaged the movement.

The Prop. 8 repeal is not the only marriage-related measure that failed to qualify for November's election. An initiative to outlaw divorce, the brainchild of Sacramento Web designer John Marcotte, missed its deadline last week.

Marcotte said he and volunteers had gathered about 8,000 signatures - they also needed about 694,000 - and said he plans to refile as well.

"We can't ask gays to shoulder the entire burden of protecting traditional marriage," Marcotte said.