How can we get the U S of A to have a Christian Democratic Party after WWII?
They might not name themselves such, but let's say that one of the Major Parties, either Democrat or Republican, have a majority of members that self-identify as Christian Democrats-- so much so that "Christian Democracy" becomes a part of the platform and self-description of that party would be enough.
One way I can see this happening is Martin Luther King surviving the sixties and becoming an elder citizen of American Politics. His views would combine leftist social justice with Christian Moralism (esp. with regards to Abortion), and although he's not terribly anti-communist, I can see him becoming one as time progresses (or at least his followers being anti-communist) as the 70s and 80s roll by. A lot of former leftists who became Neocons in OTL might become Christian Democrats instead. Any other ideas?