Not correct and that article doesn't say what you said it does. It says of the 56 founders only one was ordained clergy. Okay.

Whatever their beliefs, the Founders came from similar religious backgrounds. Most were Protestants. The largest number were raised in the three largest Christian traditions of colonial America—Anglicanism (as in the cases of John Jay, George Washington, and Edward Rutledge), Presbyterianism (as in the cases of Richard Stockton and the Rev. John Witherspoon), and Congregationalism (as in the cases of John Adams and Samuel Adams). Other Protestant groups included the Society of Friends (Quakers), the Lutherans, and the Dutch Reformed. Three Founders—Charles Carroll and Daniel Carroll of Maryland and Thomas Fitzsimmons of Pennsylvania—were of Roman Catholic heritage.

The sweeping disagreement over the religious faiths of the Founders arises from a question of discrepancy. Did their private beliefs differ from the orthodox teachings of their churches? On the surface, most Founders appear to have been orthodox (or “right-believing”) Christians. Most were baptized, listed on church rolls, married to practicing Christians, and frequent or at least sporadic attenders of services of Christian worship. In public statements, most invoked divine assistance.

https://www.britannica.com/topic/The-Founding-Fathers-Deism-and-Christianity-1272214

You can argue about how devout they were and we can never know their sincere inner belief, but you cannot say they were not majority Christian. Even the ones people point to as deists were largely raised Christian. I'm glad they were not so deranged as to make religion a part of the new government, and that they had the wisdom to write the First Amendment, the one through which all others flow, in such a way as to prohibit establishment and grant free exercise. They definitely didn't want religious dogma to play any role in governing and rightly so but it is simply not correct to say that they were other than mostly Christian in their private religious lives.

None of them were Jewish. Three of them were Catholic. What else do you think they were if not Christian?

You cite Thomas Jefferson as an example, but actually he was Christian too. The actual title of "The Jefferson Bible" you cited as evidence of his non-christianity is "The Life and Morals of Jesus of Nazareth."

About it, he wrote "A more beautiful or precious morsel of ethics I have never seen; it is a document in proof that I am a real Christian, that is to say, a disciple of the doctrines of Jesus."