In 1970, fewer than 40 secular groups lobbied Congress and the Executive Branch. Now, that number has ballooned to more than 200, with total lobbying expenditures by faith-based organizations approaching $400 million a year.

Nearly 20% of all religious advocacy is by Roman Catholics. Evangelicals account for 18%, Jews 12% and mainline Protestants 8%. Baha’is, Buddhists, Hindus, Muslims and Sikhs also have lobbied in Washington, although in much smaller numbers.

By far the biggest lobbyist was the right-wing American Israel Public Affairs Committee (AIPAC), which spent $87.9 million in 2008. In second place was the United States Conference of Catholic Bishops at $26.7 million in 2009. Third place went to another conservative group, the Family Research Council, with $14.3 million in 2008.