Hey, I really recommend The Faiths of the Founding Fathers by David Holmes.
Holmes take a really good look at what these guys professed to believe, and also how they followed through. He makes no judgements, just presenting the best of the historical record.
Turns out that the majority of the Founders tried to follow the moral principles of Jesus, but much like lots of original Christians, most questioned the divinity of Jesus. For example, Jefferson made a Bible just from the words of Jesus, which is a Bible most anyone can believe in, even though we now know that there was a lot of tinkering with it. (See "Misquoting Jesus" by biblical scholar Bart Ehrman.)
As a result, most of the Founders identified as different kinds of Deist, though one Unitarian became president.
This is making me question my own faith; I now identify with Ben Franklin, George Washington, and Thomas Jefferson…