I'd argue CCM is probably even more right-wing than country, which is at least big enough that it picks up at least some liberals. I imagine Democrats that listen to Christian rock/pop are pretty rare, and most religious minorities tend to listen to gospel.
Failing that, dead0man/RINO Tom probably got it right with classic Southern rock.
Eh, most CCM you hear on the radio is so bland and inoffensive that I have a hard time believing there aren't a fair number of liberal Catholics/Mainline Protestants who listen to it. The stereotype would be liberal Christian suburban moms just looking for something upbeat and positive for their kids.
Now, if you're talking Hillsong/Bethel-style evangelical worship music, then that's almost certainly highly Republican.
