In 1934, Hoffman ran as the Republican candidate for Michigan's 4th congressional district, defeating incumbent Democrat George Ernest Foulkes. Hoffman was elected to the Seventy-fourth United States Congress and was re-elected to the thirteen succeeding Congresses, serving from January 3, 1935 until January 3, 1963. He was seen as "a bitter lone wolf" during much of his time in office, unable to work with either the Democrats or the Republicans. Hoffman voted against the Civil Rights Acts of 1957 and 1960, as well as the 24th Amendment to the U.S. Constitution.