"Ken Mehlman, a former Republican Party chairman who is openly gay and was active in the New York lobbying effort, puts it more bluntly. Same-sex marriage is a more successful part of the liberal agenda, he contends, because it’s not necessarily liberal. “This is an issue where there are important conservative arguments for people being treated equally under the law,” he said. “If you believe in maximum freedom and that it’s important to promote strong families and that the golden rule is a good thing to follow, all of those things argue for allowing people to marry the people they love.”"
I think there's a substantial consensus that the Republican Party in its current formulation is not stable, and that both parties are lagging a nationwide trend in favor of gay marriage. Mehlman is attempting to carve out space for a not-Democratic Party that has some ideological cohesion but does not revolve around hating gays and abortion.
There are a lot of efforts around in the country at every level to redefine what it means to be Republican. I think this is visible in things like the anti-collective bargaining legislation (individualism! That's ideologically coherent for Republicans. Also pro-business. Very coherent). But there's also a lot of the same-old-same-old (protecting corporate tax breaks and generally making the tax code more regressive, not to mention cutting funding for Planned Parenthood and writing regulations to eliminate providers of abortions). I don't think the Party has much of a chance of surviving on the same-old-same-old alone; however, that doesn't necessarily predict where it will go in the future -- or even if it will continue to exist as "The Republican Party". One of the effects of recent Supreme Court cases like Citizens United has been to make it possible to dismantle many of the functions of a political party (fund raising in general and Get Out the Vote efforts) and have decentralized organizations fulfill them in a less-transparent way.
But I think you cannot get away from needing a slate of candidates and a rhetorical structure and/or ideology to hold it all together. That is the piece in contention right now.
ETA: R. and I had no answer between us to the following question: is there a conservative population which could be described as "pro gay marriage" as a family values issue, but which would continue to oppose reproductive rights?
Such a population _does_ exist and is probably best represented by this group:
I'm unclear on the status of the Log Cabin Republicans on the reproductive rights issue -- and I think everyone else is a little unclear on it, too.