Republican Ryan Fazio defeated two other candidates to win the Aug. 17 special election for the vacant 36th Senate District seat.
The seat, which includes Greenwich and parts of Stamford and New Canaan, was held by Democrat Alex Kasser, who resigned unexpectedly June 22.
Fazio defeated Democrat Alex Gevanter, an attorney and former leader of the Connecticut chapter of Moms Demand Action for Gun Sense in America, and petitioning candidate John Blankley.
Fazio had 50% of the vote, with Gevanter taking 48% and Blankley, 2%. Turnout was 24% of the district's registered voters.
Kasser first won the seat—held by Republicans for almost a century—in 2018, defeating long-term incumbent Scott Frantz.
She retained the seat last year, winning 51% of the vote against Fazio, a member of the Greenwich Town Meeting.
Fazio will serve out the remainder of Kasser's term, which runs through 2022.
Democrats now have a 10 seat margin in the state Senate, although Fazio's win means the party loses its super majority in the chamber.