Republican presidential candidate Texas Gov. Rick Perry speaks to supporters at Tommy's Ham House in Greenville, S.C. (AP Photo/Richard Shiro, File)

The clash is between two converging branches of the conservative movement: the social conservatives who wants to outlaw gay marriage at all costs, and the newly in vogue brand of tea party federalists holding that, regardless of how you feel about the controversial issue, it’s a matter for the states.

Already, 2012 presidential contenders and tea-party favorites Rick Perry and Michele Bachmann (R-Minn.) have essentially taken both sides – supporting the idea that states should have the right to decide the issue but also backing a federal amendment defining marriage as between one man and one woman. That amendment, of course, would effectively take the issue out of the states’ hands, so it’s hard to marry (no pun intended) the two positions.

At a debate a couple months ago, Rep. Bachmann even took those two positions in the space of a few minutes. For Gov. Perry, his position has been a little unclear for a while now – at least, until the Texas governor signed a pledge Friday favoring a constitutional amendment. (A good recap here.)

So why is this such a tough issue to pin down?

Polling tells the story of a very divided GOP.

An increasing number of tea partiers and Republicans, concerned about the size of the federal government, want a return to a more federalist model of government, with state and local governments deciding more of the day’s key issues.

For some, that includes the definition of marriage. That’s why, when New York passed its gay marriage law a couple months ago, Perry said he was okay with it. Bachmann likewise has said that she respects New York’s right to define marriage – citing the 10th amendment.

More recently, though, both Perry and Bachmann have assured voters that they support a marriage amendment.

In many ways, their seeming inconsistencies on the issue reflect a conflicted Republican Party on gay rights.

Almost all of the Republican presidential field has come out in support of an amendment banning gay marriage, with all but Rep. Ron Paul (R-Texas) and Herman Cain favoring the amendment at a June debate. Former Utah governor Jon Huntsman, who joined the race later, favors civil unions for gay couples and has said he would respect New York's new law.

Republicans broadly are very much against gay marriage. But according to a survey by the Public Religion Research Institute last September, by a 55-to-41 percent margin, they think decisions about the issue should be made at the state level. And among tea partiers, the margin is even greater: 62 to 35 percent.

So, at least on the surface, that’s a solid majority of Republicans AND tea partiers expressing what amounts to opposition to a federal marriage amendment.

Now it should be noted that, as with Bachmann and Perry, there does appear to be some overlap between those who say they think gay marriage is a state issue and those who support a federal amendment effectively banning gay marriage. But even if you allow for those apparently contradictory stances, there has been a significant shift towards states’ rights in recent years.

The numbers lean significantly more towards states’ rights than when the Pew Research Center tested a similar question in 2006. Then, more Republicans (49 percent) favored the federal government deciding the issue than the states (44 percent).

The numbers follow a broader movement toward a more federalist approach to government, with Pew polling last year showing 58 percent of respondents saying that “the federal government is interfering too much in state and local matters.”

That doesn’t mean, of course, that federalism is anything new. In fact, for a while now, there has been a pretty wide gap between opposition to gay marriage and support for a constitutional amendment on it. A 2004 Washington Post/ABC News poll showed that, while 55 percent of people thought gay marriage should be illegal, just 38 percent said there should be a federal amendment banning it.

While opposing gay marriage has been a relatively easy call for Republican candidates for decades, the emerging strand of federalism – largely an outgrowth of the tea party movement – throws things out of whack.

The last thing someone like Bachmann or Perry wants to do is alienate social conservatives, particularly given their influence in Iowa, the home of the first caucuses. But the candidates have also got to remember where their tea party bread is buttered, and if they stray too far from the emerging federalist trend, they could lose some of that tea party support.

Look for both of them to have to nail down their position even more in the coming weeks and months. Pleasing both sides won’t be easy.

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