Troy Stevenson, executive director of Garden State Equality, spoke at a Sept. 27 news conference in Montclair, N.J., after a state judge made same-sex marriages legal. (Julio Cortez/AP)

Few elected Republicans support giving gays the right to marry. The party’s influential social-conservative wing sees “traditional marriage” as a defining issue. And while most major Democrats are rushing to embrace same-sex marriage, none of the most prominent potential Republican presidential candidates have taken that step.

But a powerful group of Republican donors, who see the GOP’s staunch opposition to gay rights as a major problem, is trying to push the party toward a more welcoming middle ground — where candidates who oppose marriage rights can do so without seeming hateful.

The behind-the-scenes effort is being led largely by GOP mega-donor Paul Singer, a hedge fund executive whose son is gay, and former Republican National Committee chairman Ken Mehlman, who revealed his homosexuality in 2010, long after he had left the GOP leadership.

Singer’s advocacy group, the American Unity Fund, has been quietly prodding Republican lawmakers to take a first step toward backing gay rights by voting for the Employment Non-Discrimination Act. The measure, which is expected to come to the full Senate for a vote as early as this month, would ban workplace discrimination on the basis of sexual orientation or gender identity.

Singer’s group recently hired as lobbyists two former GOP lawmakers, Tom Reynolds (N.Y.) and Norm Coleman (Minn.), who say they oppose same-sex marriage but support workplace protections for gays.

Armed with new polling data and talking points, organizers are coaching lawmakers and potential candidates on politically smart ways to talk about gay rights to reassure general-election voters while not alienating core conservatives.

A softer GOP approach, they argue, would boost the party’s chances with young voters, women and centrist independents, all of whom tend to be supportive of gay rights and have drifted away from the party.

One poll-tested sound bite being suggested to candidates references the Golden Rule — to “treat others as we’d like to be treated, including gay, lesbian and transgender Americans.” The line, according to a memo from a GOP polling firm hired to guide the campaign, wins support from 89 percent of Republican voters.

“The Republican image, unfortunately, is one in which we have an empathy gap,” Coleman said. “That impacts us across the board. An issue like this, which is about being against discrimination, feeds into the long-term future of the party. It addresses one of the negatives that we are facing today.”

Some pro-gay-rights Republicans point hopefully to New Jersey Gov. Chris Christie as a case study of a GOP politician who seems to be looking for a politically viable approach. The governor, expected to easily win reelection next month, is close to Singer, though aides to both men declined to discuss their private conversations about the issue.

Christie won praise from social conservatives last year for vetoing a same-sex-marriage bill. But he also routinely voices sympathy for gays; in a debate last week, for instance, he said that if one of his children came out, he would “grab them and hug them and tell them I love them.”

Christie, who has said he does not see homosexuality as a sin, nominated an openly gay judge to the state Supreme Court and, in August, signed a law banning licensed therapists from practicing gay conversion therapy on minors. LGBT activists hailed an anti-bullying law he signed as one of the country’s toughest measures protecting gay children.

Christie’s opposition has not been enough to block same-sex marriage in New Jersey.

A state judge ruled last month that gay marriage should be legal, clearing the way for same-sex nuptials to begin this week. The Christie administration appealed. State supreme court oral arguments had been planned for January, but the justices ruled last week that weddings should be allowed to proceed immediately. On Monday morning, with weddings already taking place, Christie announced that his administration was dropping its appeal – in effect making same-sex marriage the law of the land in New Jersey.

Gay rights activists, meanwhile, are rallying votes in the legislature on a second track, to override the governor’s veto of the marriage bill.

Troy Stevenson, executive director of Garden State Equality, said his group has a closer relationship with Christie than it had with his Democratic predecessors. Like other activists, he sees the governor’s stance on marriage as an anomaly most likely attributable to calculations around his presidential ambitions.

“I honestly don’t see what is holding him back” from supporting same-sex marriage, Stevenson said, “except for potentially politics.”

Organizers of the pro-gay Republican effort say they remain committed to pressing for marriage rights, with Singer and Mehl­man both backing a number of state-level campaigns — including the push to override Christie’s veto.

“But we’re telling Republicans, ‘If you think you can’t get there on marriage, here is a safe list of things you can support,’ ” said Jeff Cook-McCormac, senior adviser to Singer’s advocacy group.

Organizers say they are confident that the Senate will pass the Employment Non-Discrimination Act (ENDA). The Republican-led House, they say, is a taller order, though they note that Rep. Paul Ryan (Wis.), the party’s 2012 vice-presidential nominee, has voiced support for workplace protections in the past.

Social-conservative leaders say the effort by gay rights backers won’t work.

“Regardless of how much money [Singer and his allies] bring to the table, it is not to the advantage of Republican officeholders politically to support his agenda,” said Peter Sprigg, senior fellow for policy studies at the Family Research Council, one of the major evangelical groups opposing the ENDA. “Particularly in Republican primaries, the Republican Party is still strongly socially conservative. These are core convictions that people have.”

Sprigg described the ENDA as a “legislative way to declare that it’s morally wrong to disapprove of homosexual conduct.” The bill, he said, is a “direct attack against the moral convictions of social conservatives.”

In their lobbying appointments and meetings with candidates and strategists, advocates argue that politicians need not fear a backlash should they decide to change course on gay rights issues.

“Because it’s so personal, we are helping them through the process and helping guide them, and showing them that Republican support is there in the electorate, that they’re not going to be punished,” said Dan Meyers, a former RNC staffer who is president of Project Right Side, an advocacy group rolled out by Mehl­man after the 2012 elections.

Increasing pressure is also coming from Republican donors who see gay rights as a determining factor in who gets their checks. The issue routinely comes up at New York GOP fundraisers, Cook-McCormac said, “always in the context of, ‘The party’s got to get over this.’ ”

New data being circulated by the campaign show that a clear majority of Republicans back the workplace anti-discrimination law. In contrast, though support for same-sex marriage has been rising among GOP voters, it remains a minority view in the party’s electorate.

Reynolds voted against the ­employment-protections bill in 2007. At the time, he said, he saw it as a “trial lawyer bonanza.” But similar state laws have not sparked frivolous lawsuits, he said.

“There just doesn’t seem to be evidence of some of the concerns that were presented at the time,” he said.

The outreach to GOP lawmakers is closely aligned with a $2 million pro-ENDA lobbying campaign being run by a new bipartisan coalition called Americans for Workplace Opportunity. Singer has forged an unusual partnership with a liberal Democratic donor, Jonathan Lewis, with each pledging $250,000 for the effort.

Singer said the ENDA is “an opportunity for Republicans to do what is right and reinforce the American principle that people should be judged on their merits.”