Foot was a member of the Connecticut House of Representatives in 1817 and 1818, and was elected to the Sixteenth Congress, serving from March 4, 1819 to March 3, 1821. He was again a member of the State house of representatives from 1821 to 1823 and 1825 to 1826, serving as speaker in 1825 to 1826; he was elected to the Eighteenth Congress, serving from March 4, 1823 to March 3, 1825. He was elected by the General Assembly to the U.S. Senate as an Adams' man (later Anti-Jacksonian) within the splintering Democratic Republican Party. He served in the Senate from March 4, 1827 to March 3, 1833. In the Senate he is most noted for the "Foot Resolution" of December 29, 1829 to limit the sale of public lands. It was during debate on this resolution that Daniel Webster gave his "Liberty and Union, one and inseparable, now and forever" speech.