An interesting snapshot, from the Pew Forum:
The newly elected, 113th Congress includes the first Buddhist to serve in the Senate, the first Hindu to serve in either chamber and the first member of Congress to describe her religion as “none,” continuing a gradual increase in religious diversity that mirrors trends in the country as a whole. While Congress remains majority Protestant, the institution is far less so today than it was 50 years ago, when nearly three-quarters of the members belonged to Protestant denominations.
Catholics have seen the biggest gains among the 530 seats in the new Congress that have been decided as of Nov. 16. So far, Catholics have picked up five seats, for a total of 161, raising their share to just over 30%. The biggest decline is among Jews, who have been elected to 32 seats (6%), seven fewer than in the 112th Congress, where Jews held 39 seats (7%). Mormons continue to hold 15 seats (about 3%), the same as in the previous Congress.Protestants also appear likely to continue to occupy about the same proportion of seats (56%) as in the 112th Congress (57%). In addition, the Protestant share of each political party in the new Congress is about the same as in the 112th; roughly seven-in-ten Republicans are Protestants, compared with fewer than half of Democrats. However, the members elected for the first time in 2012 are less Protestant than the group first elected in 2010; 48% are Protestant, compared with 59% of those elected for the first time in 2010.
Protestants, Catholics and Jews each make up a greater percentage of the members of Congress than of all U.S. adults. The same is true for some sub-groups of Protestants, such as Episcopalians and Presbyterians. By contrast, Pentecostals are a much smaller percentage of Congress than of the general public. Due in part to electoral gains in recent years, Buddhists, Muslims and Hindus now are represented in Congress in closer proportion to their numbers in the U.S. adult population. But some small religious groups, such as Jehovah’s Witnesses, are not represented at all in Congress.