Gov. Rick Perry’s credibility on social conservative issues has been under attack from Mike Huckabee recently, so it’s mildly surprising to see him take such a moderate position on gay marriage:

“Our friends in New York six weeks ago passed a statute that said marriage can be between two people of the same sex. And you know what? That’s New York, and that’s their business, and that’s fine with me,” [Perry] said to applause from several hundred GOP donors in Aspen, the AP reported.

“That is their call. If you believe in the 10th Amendment, stay out of their business.”

The most significant part of this story? Perry was applauded by Republican donors for supporting New York’s decision. Add this to Mitt Romney and Tim Pawlenty pointedly refusing to sign an anti-gay-marriage pledge (which was admittedly problematic for other reasons), and it seems like staunch opposition to same-sex marriage may no longer be a requirement for Republican presidential candidates. It was one thing for a moderate New York Republican like Rudy Giuliani to take the states’ rights position in 2008, but there’s a serious transformation in the movement if a socially-conservative Texas governor is now making the same argument.

And the reason is because the issue is becoming less important to the conservative movement as a whole, a shift that’s driven by both cultural changes across the nation and a reemphasis on economic concerns. Perry will alienate some social conservatives with his stance, but the states’ rights argument is very attractive to the other more libertarian segments of the conservative movement.

Interestingly enough, the states’ rights argument isn’t just being used by conservatives. President Obama has also used it to support the decision in New York, while maintaining that he’s still not personally in favor of gay marriage. It’s a simple transition line for Democrats who aren’t yet ready to fully support same-sex marriage, and for Republicans who are no longer comfortable fully opposing it.