So much for the surface. But to indulge in second thought is to find a somewhat different story. It is impossible to think of American politics as immune to religious impact. Al Smith in 1928 was unacceptable to many Baptists in the southern Bible Belt. In 1960 Jack Kennedy went there to make an explicit and convincing demonstration of resolve to keep his religion and his presidency in separate compartments.
Most presidents are or become churchgoers.
One can hardly consider Rev. Martin Luther King or Rev. Jesse Jackson as beyond politics. No religious Jew has ever become president. Abolition, Women's Suffrage, Prohibition, Civil Rights, Abortion. The fact is that if you really believe in democracy you cannot realistically leave the influence of the Church out of the equation. Nor is religion's participation confined to the highly focused function of elective politics.