A special election was held in in 1817 to fill two vacancies in the 15th Congress, both of which had occurred before the start of that Congress. The vacancies were left by the death of members-elect Sylvanus Backus (F) on February 15, 1817, and Charles Dennison (F) who declined the seat.
As there were two vacancies in an at-large district, the top two candidates were elected to represent Connecticut.
Huntington and Terry took their seats with the rest of the 15th Congress.