A cursory examination of the percentages of US Congressmen by religion, revealed that Judaism is way over-represented in terms of the percent of the population, though not nearly so much so as Christians.
On a positive note, one can, potentially, be Jewish and also an atheist, so maybe some Congress persons who identify as Jewish, are actually atheists. (I know, I’m grasping at straws.)
The most under-represented is “no affiliation" (only 1 congress-person is listed as “none"). So that is a small fraction of 1%, when compared to the population of persons in the US who are unaffiliated with any religion, which is close to 20%.
There is 1 Muslim, and a small number of Hindu and Buddhists (1 or 2 or so, not sure), but these religions are a pretty small portion of the US population.
I didn’t look as closely at the member’s racial identity, but if we’re talking Hispanics, there ARE (white) Hispanic Republicans in Congress.
There are a good percentage of black congress persons (all democrats), but I’m not sure that it is up to the % of blacks in the US population.