Dates in office: January 9, 1923 - April 4, 1923
Born: October 14, 1880
Died: September 1, 1972

Mike Donnelly, Sr. was born in Missouri and came to Oklahoma City in 1904. Donnelly served as Mayor of Capitol Hill prior to its annexation by Oklahoma City in 1911.  He also served as the Chief Clerk of the City’s Water Department. 
Donnelly became Acting Mayor upon Mayor John Walton’s becoming Governor in January 1923 and completed the remainder of Walton’s term. He later served as an Oklahoma County Commissioner from 1934 to 1948.