Of the 44 U.S. presidents, all but a handful have been affiliated with a relatively narrow list of traditional Protestant denominations.
Eleven were Episcopalians (12 if you count Thomas Jefferson, whose adult beliefs are a subject of debate), eight were Presbyterians, four were Methodists and four were Baptists. Others included Congregationalists, Dutch Reformed and Disciples of Christ.
President Obama attended Trinity United Church of Christ in Chicago, a congregation with traditional Protestant roots despite its untraditional pastor, the Rev. Jeremiah A. Wright Jr. In Washington, Obama has attended services at mostly black Protestant churches.
The only chief executive whose roots were clearly outside that mainstream tradition was John F. Kennedy, a Roman Catholic.
http://www.latimes.com/news/opinion/commentary/la-oe-mcmanus-column-religion-politic20110605,0,1204800.column