Actually, many errant Catholics are socialists. The Catechism specifically addresses socialism and states the Church has rejected the totalitarian and atheistic ideologies associated in modem times with "communism" or "socialism." and "Regulating the economy solely by centralized planning perverts the basis of social bonds.
That does not explain the many Protestants socialists, one of whom occupies the White House now.
While I'm sure that there are Protestants who do indeed live in the White House, I can't think of any mentioned by name.