Very religious Americans remain significantly more likely than those less religious to identify as Republicans or lean Republican, and nonreligious Americans are more likely to identify as Democrats or lean Democratic. This strong relationship between religion and party identification has persisted over the past three years and four months, regardless of overall, broad partisan changes....
The detailed breakdown of approximately 30,000 interviews conducted in May 2011 shows that very religious Americans are 19 percentage points more likely to identify as Republicans than are the nonreligious, 48% vs. 29%.
Very religious Americans are 10 points more likely to be Republican than Democratic -- 48% vs. 38%. Among moderately religious Americans, there is a Democratic advantage of 8 points. Among nonreligious Americans, the Democratic advantage increases to 25 points.
At The Atlantic, Chris Good notes that religious affiliation is an advantage for Michele Bachmann in the Iowa caucuses:
Working to her advantage in Iowa is this possibly overlooked facet of her political identity: She can pull support both from evangelical Christians and from tea-party Republicans and independents, two important groups that overlap. GOP political infrastructure is heavy on evangelical influence in Iowa, where conservative Christian groups hold public events and can broker support. Bachmann is an evangelical Christian herself and has taken conservative stances on social issues.At the Washington Post, Elizabeth Tenety writes:
A 2005 study by Barna revealed that 83 percent of Americans said they had prayed in the last week, putting Bachmann well into the devout mainstream. Politicians, like many religious people, talk about their faith because it is central to how they see the world, and because it’s a language that many voters understand. But Bachmann’s political reach may be limited, as the Pew Forum on Religion and Public Life found that only 26 percent of Americans identify as evangelical Protestants, and her distinctly Christian approach to her political vocation may not resonate with a wider audience.