Jefferson was very influential in the formation of the Constitution even though he wasn’t there for the debates. I'm currently reading "What Kind of Nation: Thomas Jefferson, John Marshall, and the Epic Struggle to Create a United States" by James F. Simon. In it Simon points out that Jefferson played no part in the creation of the Constitution. In fact his initial reaction to Madison's creation was decided unenthusiastic, and he was always a reluctant supporter.
Jefferson's earlier wrightings were very influential in the writing of the constitution. Jefferson was supicious of government power. That is consistant in all his writing. He was as supportive of the constitution as he was of any government.