Sumner was elected as a Republican to the Seventy-sixth and to the three succeeding Congresses (January 3, 1939 – January 3, 1947). She was not a candidate for renomination in 1946.
She resumed position as vice president from 1938 to 1966, and president from 1966 to 1994, of Sumner National Bank. She was a resident of Milford, Illinois, until her death in Watseka, Illinois, on August 10, 1994.