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.