Asking the "Odd Fellows" if this is a Christian Nation?

I found the description of Thomas Jefferson and John Leland as the “religious odd fellows” intriguing.  Kidd mentions this “friendship” numerous times throughout the book.  He states, “To say that Jefferson and Leland made religious odd fellows is an understatement.  Leland had devoted his life to saving souls and would estimate at the end of his career that he had preached about 8,000 sermons” (5) and “baptized 1,278 converts and itinerated distances across America that together would add up to three trips around the Earth...”(208)  Jefferson, on the other hand, did not believe that the blood of Jesus would save him or anyone else, although he attended church regularly as president” (5).  Yet, Leland “was his most outspoken Baptist supporter” (239).

In the epilogue, Kidd states that “whether by emphasizing the need for the virtue, claiming God’s providential blessings,or articulating equality by creation, clearly, religion played an indispensable role in shaping the origins of the American Republic.  Although leaders from Thomas Jefferson to John Leland held highly dissimilar personal beliefs, Americans united around public religious principles to inspire the Revolution and to articulate the basis for American rights” (253).  

Kidd then asks what appears to be the million dollar question:  “Does the national significance of these precepts mean that America was founded as a Christian nation?” (253)  

Given the fact that this question is so prevalent in today’s political and religious culture, should a historian attempt to answer this question? Kidd provides a great answer, stating yes, but that “the founders’ religious agreement was on public values, not private doctrines” (254).  However, should one attempt to answer it?  Is there any contemporary evidence that this question – not questions such as was the Constitution Christian enough, etc – was even asked in the Revolutionary Period?  See Google N-Gram results.  Can historians, judicial scholars, etc in today’s hyper-pluralistic society ask questions like this to answer modern questions?  Would Leland and Jefferson both find this question odd had it been asked of them?  Was that really why the war was fought?  Would Leland and Jefferson both say that we are missing the point?