This report provides an interesting picture of the religious landscape of the new Congress, and even compares it with its predecessors. The authors note that Protestants are overrepresented in Congress, by comparison with their share of the population as a whole, and that the religiously unaffiliated are substantially underrepresented. Among Protestant denominations, the "old line" (Methodists, Presbyterians, and Episcopalians, for example) are overrepresented, and Baptists and Pentecostals are underrepresented. Over the long term, old line denominations have lost "market share" in Congress, while Baptists and Catholics have been among the big gainers. The "most overrepresented" groups are (in order) Episcopalians, Jews, and Presbyterians.
Are we witnessing the death of America's Christian denominations? Studies conducted by secular and Christian organizations indicate that we are. Fewer and fewer American Christians, especially Protestants, strongly identify with a particular religious communion--Methodist, Baptist, Presbyterian, Pentecostal, etc. According to the Baylor Survey on Religion, nondenominational churches now represent the second largest group of Protestant churches in America, and they are also the fastest growing.