After being admitted to the Vermont bar in 1831, Foot served as an Addison County state legislator in 1833; he was returned to state office from 1836 to 1838.
Spending just six years as a prosecuting attorney, Foot eyed a promising career in national politics.
His successful 1843 U.S. House campaign focused on 19th century conservative ideals and the call of Manifest Destiny in the frontier of the American West-although Foot, and fellow Whigs at the time, rejected the political catch phrase coined by Jacksonian Democrats.
Foot was elected as a Whig congressman from Vermont in 1843. And by 1850 he successfully transitioned his political machine to make a run for the U.S. Senate; he was elected to that post in 1850. Foot succeeded U.S. Sen. Samuel Phelps, another Whig, from Middlebury.
After the demise of the Whig Party in 1856 over the slavery question, Foote was reelected as a Republican senator; he served as senator from 1856 until his death.
Foote was president pro tempore of the U.S. Senate from 1861 to 1864 during the darkest days of the U.S. Civil War. He died, at age 63, in Washington, D.C., on March 28, 1866.