Superbelt

It wasn't a relative few. And the ones who really counted. The leaders were mostly diests. It is telling that a MAJORITY of our founders voted down this line: "Jesus Christ...the holy author of our religion." (as shown in my Jefferson Quotes). The majority of our founders wanted to keep religion out of our government. Many, despite their personal beliefs. This nation is areligious. Not athiest like communist countries. Because that is still preferential. Our government is supposed to have no commitment to any religion whatsoever.

The influences for our constitution come from many sources. We took heavily from Hammurabi's Code and Romes Twelve Tables(451 BC) as our basis for civil and criminal law. The framework for our government was directly lifted from Roman Republican Law. Specifically Polybius's History of the Rise of Rome. That is where we got our system of checks and balances. All three branches. Those sources are hardly Judeo/Christian. Other influences are: The French Declaration of rights of man, British Bill of Rights, Magna Carta, Athenian Constituion by Aristotle, the Iriquois Constitution, and Yes the Bible.
The bible was a source and influence but not a primary, God given source. It is a source of order and law from one of the worlds, great, ancient cultures. Same as the Greek, Roman and Mesopotamian sources that we also used.