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.

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 theEmployment 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.”