Go read Ross Douthat's very important column on the Catholic Church's presence in contemporary American life and politics.
The collapse in the church’s reputation has coincided with a substantial loss of Catholic influence in American political debates. Whereas eight years ago, a Catholic view of economics and culture represented a center that both parties hoped to claim, today’s Republicans are more likely to channel Ayn Rand than Thomas Aquinas, and a strident social liberalism holds the whip hand in the Democratic Party.
Indeed, between Mitt Romney’s comments about the mooching 47 percent and the White House’s cynical decision to energize its base by picking fights over abortion and contraception, both parties spent 2012 effectively running against Catholic ideas about the common good.