As serving in the Connecticut General Assembly is a part-time position, most members have full-time jobs.

Duff has worked as a realtor for William Pitt Sotheby's International Realty since 1995.

In 2001, he ran in a special election for the seat in the Connecticut House of Representatives left vacant by Alex Knopp when he took office as mayor of Norwalk.

[8] In 2004, Duff sought the State Senate seat left open by Republican Robert Genuario who became Gov.

[12] He ran against Republican Jeff Konspore, chairman of the Norwalk school board.