Kelcourse served the cities of Newburyport and Amesbury and the town of Salisbury for 4 terms in the House of Representatives.

In 2012, Kelcourse ran for the Massachusetts State Senate in the 1st Essex district as an unenrolled candidate.

On June 1, 2022, Kelcourse was nominated by Governor Charlie Baker to serve on the state Parole Board.

He resigned his position as State Representative on June 29, 2022 and was officially sworn in as a member of the Parole Board.

Prior to his appointment to the Parole Board, Kelcourse operated a legal practice in Newburyport, Massachusetts.