It is entirely possible that the top echelons of political power in the United States would be completely absent a Protestant representative. The religious affiliation could very likely look as such:
President – LDS
Vice President – Catholic
Senate Majority Leader – LDS
Speaker of the House – Catholic (Boehner or Pelosi) or Jewish (if Cantor were to stage a coup).
Supreme Court of the United States – 6 Catholic / 3 Jewish (0 Protestant)