Countryclubbers can belong to any church, but they focus on party mechanics, not policy development. Some folks misperceive the countryclubber as a large faction within the Republican party, but they're not ~ they just have a singular interest and that serves to boost the chances they'll be tapped to run for office.
This is how the Republican Party got to be called "The Stupid Party" ~ the countryclubbers have no interest in policy ~ John McCain is a good example of this attitude.
The variation in the Democrat party is that there are clusters of special interests that constitute affinity pressure groups. They provide an inordinate amount of the party infrastructure but few candidates.
Democrats are typified most by existing office holders moving up the chairs to run for higher office. The Republicans actually have non-politicians moving in and out of elective office, and that's something you never see with Democrats.