University of Chicago School of Law Professor Geof Stone has a fairly long video lecture on the Christian Nation/religion of the key Founders question. It's quite good. Stone is an ardent secular leftist and as such he overstates the Deist influence. He put Ben Franklin and Thomas Jefferson in the same box as Thomas Paine and Ethan Allen, which I would not. However, Stone does recognize the "hybrid" system that mixed elements of Christianity with Deism and properly places Washington, J. Adams, and others in that box. He actually uses the term "theistic rationalist" when discussing Washington's faith. And he also informs about how many of these "Deists" could be very pro "religion and morality" in their rhetoric and attended Christian Churches. Finally he includes some great discussion of the concept of American "civil religion" that parallels the research I've uncovered.
Check it out.