Augustine Lonergan (May 20, 1874 – October 18, 1947), of Hartford, Connecticut, was a Democratic U.S. Representative from Connecticut from 1913 to 1915, 1917 to 1921, and 1931 to 1933. He was also a U.S. Senator from Connecticut from 1933 to 1939.Lonergan was elected to the Senate by narrowly defeating Hiram Bingham III amidst the Roosevelt landslide of 1932 due to the Great Depression. But he lost re-election in 1938.