The Catholic Church in the United States is part of the worldwide Catholic Church, the Christian Church in full communion with the Pope. With more than 68.5 registered million members, it is the largest single religious denomination in the United States, comprising about 22 percent of the population. According to a new 2011 study by the Center for Applied Research in the Apostolate at Georgetown University, "The US Catholic population is currently 77.7 million." The United States has the fourth largest Catholic population in the world, after Brazil, Mexico, and the Philippines. http://en.wikipedia.org/wiki/Catholic_Church_in_the_United_States Santorum's victory last night just showed you what happens when Catholics get activated. Liberals don't want the evangelicals voting with their conscience? Watch what happens now that dems have turned 70 million registered and many more by name against the tyranny of obamacare and commie liberals. Talk about choice - 70 million are going to choose to torpedo govt mandated health care. You don't have to go to church to get catholics involved. There is a good chance a 1/3 to half the people in the room are catholic in many parts of the U.S.