On December 5, 1922, James Couzens resigned as Mayor of Detroit to accept his appointment to the U.S. Senate. Couzens was appointed by Governor Alexander Groesbeck to fill the Michigan senate seat that was vacated by the resignation of Truman H. Newberry in the wake of election campaign irregularities. Couzens went on to be elected in his own right for two additional terms before his death in 1936.
Source : Detroit Historical Society