Groups lobbying for same-sex marriage may not receive the infusion of cash President Barack Obama’s campaign took in after he announced support for their cause. But gay-rights advocates say the commander in chief built needed momentum for their cause ahead of initiatives in up to four states this fall.

Obama’s endorsement could energize a base grappling with last week’s vote in North Carolina, where residents overwhelmingly supported a constitutional amendment defining marriage as solely between a man and a woman.

“The loss in North Carolina together with the president’s strong endorsement has definitely fired up folks who want to volunteer and get involved,” said Kevin Nix of Marylanders for Marriage Equality. That group is working to retain a passed but not-yet-enacted state measure that approves same-sex marriages. Maryland voters are likely to see the matter on the November ballot.

“We’ve been having a good sense of momentum since the bill passed in March,” Nix said. “This gives another boost to the campaign as we head into the summer and fall.”

After Obama’s announcement, House Minority Whip Steny Hoyer (D-Md.) came out in support of his state’s law. So have Members in Washington state, Maine and Minnesota, where voters will consider gay-marriage initiatives on the ballot this fall.

Obama’s campaign and Democratic Party officials are spotlighting the issue in fundraising messages after the president’s re-election effort saw a surge in donations linked to the May 9 announcement.

Michael Cole-Schwartz, communications director for the Human Rights Campaign, said that even though his side has seen progress on a signature federal issue — repeal of the Defense of Marriage Act — he expects little movement on Capitol Hill for the rest of this Congress. The Senate Judiciary Committee passed, on a party-line vote, a repeal of the 1996 law, which bans federal recognition of state-authorized same-sex marriages.

The Judiciary panel’s vote “was definitely a milestone step,” Cole-Schwartz said. “There’s no appetite in the House leadership for that kind of thing — quite the opposite.”

He said the repeal measure is not likely to have the votes to carry in the full Senate and that his side is looking for a GOP co-sponsor.

Much of the HRC’s activity will instead focus on state measures. Washington state lawmakers approved a same-sex marriage law, though, like Maryland, it might face a referendum come November. Same-sex marriage supporters in Maine successfully got a measure on the ballot. And voters in Minnesota will decide whether to adopt a ban.

Cole-Schwartz said HRC will contribute money and in-kind support to activists in the states, as it did in North Carolina.

“The biggest thing we do is provide staff expertise and boots on the ground,” he said.

They won’t be alone. Opponents of same-sex marriage say their side, too, got a boost when the president publicly backed gay nuptials.

“To us, it was obvious where the president was on the issue; we’re just glad he’s finally telling the truth about it,” said Tom McClusky, senior vice president for the conservative Family Research Council Action. “In Maryland, Washington state and in Maine, what we’re hoping for is this motivates the voters.”

McClusky added that when Obama served in the Senate, the future president sent McClusky’s group a letter saying he supported marriage as between one man and one woman.

“Now, the gloves are off,” McClusky said of Obama’s reversal.

People for the American Way’s Drew Courtney said Obama’s change in position will help other Americans come to the same conclusion.

“I’ve seen reports of politicians who have been inspired to come out in support of marriage equality,” said Courtney, whose liberal organization supports same-sex marriage. “Having the president of the United States take this stand is huge. It’s an issue that Americans struggle with. Everyone has had their own evolution on this.”

The HRC’s Cole-Schwartz said the president’s announcement generated a lot of excitement in the gay-rights lobby.

“Politicians who dig in their heels on an anti-gay point of view are going to be left in the dust,” he said.