I know of Charles Carroll who signed the Declaration. If there was a second please provide.
Here is a good link.
http://errantskeptics.org/Religious-Affiliation-56-signers-DeclarationOfIndependence.htm
George Washingtons Return from Service to Mount Vernon, Christmas Eve, 1783
Remember, Remember (George Washington and Guy Fawkes Day)
A Tea Party Thomist: Charles Carroll
Americas Catholic Colony [Ecumenical]
The Catholic Church in the United States of America [Ecumenical]
Catholic Founding Fathers - The Carroll Family [Ecumenical]
Charles Carroll, founding father and "an exemplar of Catholic and republican virtue" [Ecumenical]
CITIZEN JOURNALISM: Founding Catholic [Father]
"How the Catholic Church Built Western Civilization" ( Book Review )
Name of Signer (Constitution)
Daniel Carroll Maryland Catholic
Thomas Fitzsimons Pennsylvania Catholic
http://www.adherents.com/gov/Founding_Fathers_Religion.html