If being a Christian means living in a country where a lot of people call themselves Christian, then Jefferson was one. But if it means believing in the Trinity, Virgin Birth, the Incarnation, the Bible as the inerrant Word of God, in the Resurrection and the Final Judgement, then Jefferson was not a Christian. And neither was Washington, nor Madison, nor John Adams, and certainly not Ben Franklin. Let’s be clear on this!
The true nature of Jefferson's relationship to his Creator was only known to the two parties involved; and I expect that like America itself, that relationship was a work in progress throughout Jefferson's lifetime.
Jefferson's faith is not for me or you to judge except in how the self-evident Truths therein might affect our own Individual relationship to that Creator.
I just thank God that Jefferson and his peers established a system of American Government where my daughter can explore that question for herself without the threat of being stoned to death for doing so -- or being murdered in a soccer stadium for wearing squeaky shoes.
But the fact that David Barton and the Walltards (with a forward by a Mormon no less) are trying to prop up their own stately religious authority and coercive effect by riding Jeffersonian coattails -- well, that's just laughable, and erroneously dangerous.