Happy clappy “Yuz Jay-Sus luvs me” Churchianity is a product of the Second Great Awakening, and was largely a movement of the rural masses. The founding fathers were a combination of deists, congregationalists, and Episcopalians. All were suspicious of clerical influence on the government, and most had no love for Rome.
Of course they were almost all Protestant Christians, I think that 2 or 3 were Catholic Christians.
I’m not aware of any of them that denied Christ, or that were atheists.