The increase in support for the Republican Party among a variety of religious groups is also seen across levels of religious observance. Among voters who attend religious services at least once a week, the GOP’s five-point advantage in 2008 has become an 11-point advantage in 2011 (with 52% of weekly attenders expressing support for the GOP compared with 41% who favor the Democratic Party). And among those who attend religious services less often, the Democrats’ 25-point advantage in 2008 has shrunk to 14 points in 2011.

These overall patterns are also apparent among white evangelical Protestants and white Catholics. Among evangelicals, for instance, the GOP has registered significant gains among both those who are highly religiously observant and those who are less observant. The GOP held a 47-point advantage among weekly attending white evangelicals in 2008 (70% Republican vs. 23% Democratic); in 2011, they hold a 57-point advantage (76% Republican, 19% Democratic). And the Republicans’ 15-point advantage in 2008 among white evangelicals who attend religious services less often has grown to a 26-point advantage in 2011.

In 2008, white Catholics who reported attending religious services at least once a week were evenly divided between the Democratic and Republican parties. In 2011, by contrast, 52% of weekly attending white Catholics favor the GOP compared with 40% who identify with or lean toward the Democratic Party, giving the GOP a 12-point advantage. White Catholics who attend religious services less often clearly favored the Democrats over the Republicans in 2008 (by a 54% to 38% margin), but the GOP has pulled even among this group in polling conducted in 2011.

White mainline Protestant voters who attend religious services less than once a week have also contributed to the Republican Party’s significant gains. In 2008, 46% of white mainline Protestants who attend religious services less than weekly identified with or leaned toward the Democratic Party, compared with 44% who favored the GOP. Today, more than half (51%) of white mainline Protestants who attend services less than weekly call themselves Republican or lean toward the GOP, while 39% favor the Democratic Party. Changes in partisanship have been much less pronounced among white mainline Protestants who say they attend religious services at least once a week.