Historians generally think Spinoza influenced the Founders indirectly, through Spinoza's influence on John Locke. We know Locke's library contained all of Spinoza's published work. To the extent we find Spinoza's influence on the Founders' political ideas, we fond them in similar ideas. Jefferson actually made a list of key texts he relied on and I don't believe Spinoza was on it. That does not mean Jefferson did not read Spinoza, but we can;t say for sure that he did. Again, this does not mean that Spinoza did not have an influence by way of other thinkers. Here's a link to an essay called "The Founding Fathers' Library." https://oll.libertyfund.org/pages/founding-father-s-library-a-bibliographical-essay-by-forrest-mcdonald
ALSO there are various catalogues of Jefferson's books that were made at various times during his career. I think you would have go to where these catalogues are to get a definitive answer.
This source may help: http://www.masshist.org/thomasjeffersonpapers/doc?id=catalog1783_11
