An influx of Republicans has colored the House red, but the midterm elections did little to alter the religious composition of Capitol Hill.

Like the U.S. public, Protestants make up more than half (57 percent) of the 112th Congress, and Catholics constitute roughly a quarter (29 percent), according to a study by the nonpartisan Pew Forum on Religion & Public Life.

The number of Protestants in Congress slowly has dropped from 394 in the early 1960s to 304 in 2011, declining by several percentage points each decade. This year’s congressional class added 12 Protestants, however.

Nearly seven in 10 Republicans in Congress are Protestant; and there remain a greater percentage of Methodists (10 percent), Episcopalians/Anglicans (8 percent) and Presbyterians (8 percent) in Congress than in the American public.

Baptists, by contrast, are underrepresented, according to Pew’s study: They make up nearly 17 percent of the population, but less than 13 percent of Congress.

No religious group appears to be as underrepresented on Capitol Hill as atheists, however.

About one-sixth of the U.S. population (16 percent) identifies as religiously unaffiliated, according to Pew. While six members of the new Congress don’t specify a religious affiliation, none say they are unaffiliated. Rep. Pete Stark, D-CA, has said he does not believe in God, but identifies his religion as Unitarian, according to Pew.

As the study notes, there are good reasons for representatives to keep quiet about religious doubts. According to 2010 Pew survey, more than six in 10 Americans say it is important for members of Congress to have strong religious beliefs.

There are 156 Catholics, 39 Jews, 15 Mormons, three Buddhists, two Muslims, and one Quaker in the 112th Congress. There are no self-identified Pentecostals, Hindus, Anabaptists, or Jehovah’s Witnesses, according to the study.

Pew’s study was based on a comparison of the religious affiliations of members of the new Congress with data from its 2007 U.S. Religious Landscape Survey. CQ Roll Call, a media company that covers national politics, gathered the information on the religious affiliations of members of Congress.