Fresh off their win in North Carolina, opponents of gay marriage are pushing forward to enact similar constitutional amendments in more states this fall – and to actually override pro-gay marriage legislation in two others.

Foes of gay marriage now have won 31 popular votes on the issue, and they hope to extend their gains with ballot initiatives in Minnesota, Maine, Washington and Maryland.

“North Carolina once again reminds us that there is an unshakeable majority of Americans firmly wedded to the idea of traditional marriage,” said Thomas Peters, cultural director of the National Organization for Marriage. “We look forward to seeing that movement grow in the months ahead.”

With North Carolina voters approving a constitutional amendment banning gay marriage by more than 20 percentage points, 38 states now have statutes or constitutional amendments banning same-sex marriage. For the moment, that number includes California, where a federal court has overturned its constitutional amendment, known as Prop. 8 – a decision that has been appealed and could make it to the U.S. Supreme Court. Same-sex marriage is legal in eight states, plus the District of Columbia.

Despite their loss in North Carolina, advocates of same-sex marriage are not giving up. They got a boost on Wednesday, when President Barack Obama said he supported their cause, days after Vice President Joe Biden said he was “absolutely comfortable” with same-sex marriage.

“[North Carolina] was certainly a heartbreaking loss, but the fight goes on and we will continue to march forward. We remain optimistic that we will achieve full marriage equality in all 50 states, it’s only a matter of time,” said Paul Guequierre, a spokesman for Human Rights Campaign, which works on equal rights for the LGBT community. “We know that we’ll face more referendums and we will be at the ballot boxes pushing for people to vote for marriage equality in those states where we have to do that.”

Fifty percent of Americans think same-sex marriage should be legal and bestow the same rights as traditional marriage, compared to 48 percent who don’t, according to a Gallup poll released Tuesday. Support for gay marriage fell slightly in the new Gallup poll from a record high of 53 percent in 2011 -- the first time a majority of Americans favored gay marriage -- while opposition rose from 45 percent.

Opponents of same-sex marriage discount national polls and say they are plugging away at getting marriage defined as between one man and one woman in all 50 states: They are campaigning for a constitutional amendment that will go before voters in Minnesota, and are opposing an initiative that would provide for same-sex marriage in Maine. They are also working on gathering enough signatures to overturn statutes in Maryland and Washington state that legalized gay marriage, and are giving $2 million to efforts to unseat Republicans who helped the legislation pass last year in New York.

First Read: Obama's careful line on same-sex marriage
Gay marriage opponents: North Carolina no longer 'vulnerable' 

“The only poll that matters is the vote that happens the day of the election in every state,” Peters said. ”We won 31 times ... so 33, 34, 35 doesn’t seem so unlikely.”

In Maryland, supporters of gay marriage knew their opponents would push for a voter referendum after state lawmakers approved gay marriage earlier this year. They expect the referendum to make it on the ballot, because the number of signatures required is relatively low at 56,000, said Kevin Nix, a spokesman for Marylanders for Marriage Equality.

“There’s no doubt that we’re disappointed from [Tuesday] night. So, I think that what happened in North Carolina serves as a wake-up call … to re-motivate everybody,” he said, noting he thought the vote in Maryland would be a “nail biter” but was optimistic they would prevail.

In Washington state, opponents of gay marriage have collected 70,000 signatures out of 120,577 needed by June 6 to get the issue on the November ballot, said Christopher Plante, deputy campaign manager for Preserve Marriage Washington. He believes they will get the signatures they need.

“... the vote in North Carolina being so overwhelming in going 'against the tide’ of the polls and all of the pundits who said it was going to be too close to call, will certainly encourage Washington voters and Washington marriage supporters to continue this fight and to bring it to fruition,” he said.

While the North Carolina outcome appears to have emboldened opponents of gay marriage -- especially after a vacuum of four years since the last vote on a constitutional amendment on the issue -- same-sex marriage advocates should take heart, said John Dinan, a professor of political science at Wake Forest University.

“It’s a long-term effort to ... educate residents of the state about your arguments, about your concerns and about, ultimately, your cause,” he said. “It was a loss, but could also be seen as part of an overall stepping stone” in a longer campaign. 

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