Pew Research Center, Faith on the Hill: The Religious Composition of the 118th Congress:

As it begins its 118th session, the U.S. Congress remains largely untouched by two trends that have long marked religious life in the United States: a decades-long decline in the share of Americans who identify as Christian, and a corresponding increase in the percentage who say they have no religious affiliation.

Since 2007, the share of Christians in the general population has dropped from 78% to its present level of 63%. Nearly three-in-ten U.S. adults now say they are religiously unaffiliated, describing themselves as atheist, agnostic or “nothing in particular,” up from 16% who did not identify with a religion 16 years ago. But Christians make up 88% of the voting members of the new 118th Congress being sworn in on Jan. 3 – only a few percentage points lower than the Christian share of Congress in the late 1970s. In the 96th Congress, which was in session in 1979-1980, 91% of members of Congress identified as Christian. …

Both the Senate and the House are numerically dominated by Christians, with each chamber having a similar Protestant majority (57% in the House, 56% in the Senate). Looking at Protestant subgroups, Baptists make up a slightly larger share of the House (13%) than the Senate (10%). Episcopalians, Presbyterians, Lutherans and Congregationalists comprise larger shares in the Senate than in the House.

Catholics account for a slightly greater share of House than Senate members (28% and 26%, respectively). There are eight Orthodox Christians in the House, but none in the Senate.

Looking at non-Christian religions, Jews have a wider presence in the Senate (9%) than in the House (6%). There is one Buddhist in the House, Democratic Rep. Hank Johnson of Georgia, and one in the Senate, Democrat Mazie K. Hirono of Hawaii. All of the Muslims, Hindus and Unitarian Universalists in Congress are in the House.

• Christianity Today, Congress Remains Far More Christian than the Country
• Christianity Today, Evangelicals in Congress Prefer Generic Labels
• The Hill, Incoming Congress Doesn’t Reflect Religious Makeup of Constituents: Report
• PBS, Religiously, Congress Doesn’t Reflect Modern America, Pew Finds
• The Times of Israel, Christians, Jews Punching Above Demographic Weight in US Congress, Pew Finds

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