Bennett was born in Garden, Michigan, attended the public schools there and graduated from Watersmeet High School. He graduated from Marquette University Law School, Milwaukee, Wisconsin, in 1925, and took a post-graduate course at the University of Chicago Law School in 1926. He was admitted to the Wisconsin bar in 1925 and to the Michigan bar in 1926. He practiced law in Ontonagon, Michigan, from 1926 through 1942. He was prosecuting attorney of Ontonagon County 1929-1934 and the deputy commissioner of the Michigan Department of Labor and Industry 1935-1937.

Bennett was unsuccessful in his first two attempts for a seat in the United States House of Representatives, losing in 1938 and 1940 by Frank E. Hook. In 1942, Bennett prevailed over the Democrat Hook, and was elected as a Republican from Michigan's 12th District for the Seventy-eighth Congress, serving from January 3, 1943 to January 3, 1945. In 1944, Bennett lost the election to Hook, but defeated Hook again in 1946 for election to the Eightieth and to the eight succeeding Congresses, serving from January 3, 1947, until his death in Chevy Chase, Maryland in August of 1964. In Congress, Bennett was a moderate Republican who mostly opposed civil rights bills but finally voted for the Civil Rights Act of 1964 shortly before his death. He is interred in Gate of Heaven Cemetery, Silver Spring, Maryland.