he was a railroad builder, and was secretary of the androscoggin & kennebec railroad (later the maine central railroad). benson was elected member of the maine house of representatives, and served in the maine state senate. he was elected maine secretary of state in 1838 and in 1841. he was an overseer of bowdoin college 1838–1876 and president of the board for sixteen years. he served as chairman of the winthop board of selectmen 1844–1848. benson was elected as a whig to the (thirty-third congress) and as an opposition party member to the thirty-fourth congress (march 4, 1853 – march 3, 1857). he was chairman of the committee on naval affairs (thirty-fourth congress).