He moved to Eaton Rapids, Michigan. He came to Stillwater, Minnesota in 1847. He moved to St. Paul, Minnesota in 1850. He went to Mankato, Minnesota in 1857. He moved to Wells, Minnesota in 1871. He moved back to Mankato some time before serving in the Minnesota Senate from 1874 through 1877.
He "had been active in the organization of the Republican party in Minnesota." He was chosen by the Republicans to serve in the United States Senate. (Folwell. A History of Minnesota.)
"Early in the session, December 15, Hon. Morton S. Wilkinson, Republican, was elected U.S. Senator, over and in place of Gen, James Shields, Democrat. Senator Wilkinson was a staunch Free Soiler." (Sanborn, Gen. John B. "The Work of the Second Legislature, 1859-60." Collections of the Minnesota Historical Society, St. Paul: the Society, 1905, Vol. 10, Part 2, p. 623)
He was an unsuccessful Whig Party candidate for the Minnesota Territorial Council in 1853. He was elected by the Republicans to the United States House of Representatives in 1868. He was elected to the Minnesota Senate as a Democrat. He was also a member of the Free Soil Party. (Minnesota in Three Centuries, 1908)
He was an unsuccessful candidate for reelection to the United States Senate in 1864.
Biographical Sketches of the Officers of the State Government of Minnesota and of the 19th Minnesota State Legislature, by C.L. Hall, 1877, and the Biographical Directory of the United States Congress list his birth month as January. Minnesota in Three Centuries lists June.
He died in Wells, Minnesota. He was buried in Glenwood Cemetery, Mankato, Blue Earth County, Minnesota.