I’m also a little late in noticing this very well-done review by Patrick Allitt (history, Emory), some of whose on-line courses I have listened to in the car.  He discusses a book by Gregg Frazer, The Religious Beliefs of America’s Founders: Reason, Revelation, Revolution (2012).  A bit from Professor Allitt’s thoughtful conclusion:

I learned much from The Religious Beliefs of America’s Founders, but closed it unsure of how the author would address two possible criticisms. First, he offers a narrow definition of “Christianity” likely to offend many readers. Millions of liberal Protestants today would certainly describe themselves as Christians while actually holding to a faith Frazer himself would call theistic rationalism. In his view, it’s not enough to call yourself a Christian; you must also affirm the doctrinal fundamentals. He comes from a circle of evangelical historians that has transformed American historiography in the last 30 years. Its superb leading figures—George Marsden, Nathan Hatch, and Mark Noll—have forced American historians to take evangelical religion more seriously than ever before as a major factor in the nation’s history. So far as I know, however, they never denied the term “Christians” to members of the diverse groups that make up most of the American religious landscape.

Second, and on a closely related matter, Frazer never says of most figures in his book whether they did or did not call themselves Christians. It is clear that Washington and Franklin avoided using the term and that Jefferson only occasionally accepted it. But what about Madison, Gouverneur Morris, James Wilson, or Alexander Hamilton? Frazer admits that the evidence about them is rather more ambiguous but never says outright whether they accepted or applied the term to themselves. In other words, while adding “theistic rationalism” to “deism” and “Christianity” as possible categories of belief among America’s founders, he has shrunk “Christianity” to mean rather less than it did at the time of the Revolution itself.