People who attend religious servicescregularly indeed are far more likely to vote Republican. I recall that when Michael Barone analyzed the exit polls from the 2000 presidential elections he found that the only group whose Bush vote percentage did not increase among the subset who attend religious services on a regular basis were black Protestants (who voted overwhelmingly for Gore irrespective of how religious they were).
Doesn’t surprise me since that particular crowd uses Christianity as a fig leaf for their main religion of getting free stuff from the government.