I wasn't thinking of race, instead they could have done Catholics (biggest church), Southern Baptist (second biggest church), the rest of the Protestants, and then Mormon.
That would have given us more perspective and context for where these groups are.
These can be confusion with these numbers. If you divided Catholics between white and Hispanic, you would find white Catholics much more conservative than Catholics as a whole. Same thing with Baptists, white vs. black Baptists.
Should Gallup have divided the religious groups into white and minority members? That is debatable.