McCarthy-Vahey won the primary Tuesday by more than 300 votes, the Connecticut Secretary of the State's office announced.
U.S. Rep. Jim Himes (D-4th District) tweeted his congratulations to McCarthey-Vahey, "And congrats to Cristin McCarthy Vahey in Fairfield! Great set of candidates in Fairfield."
In November, McCarthy-Vahey will face Republican candidate Carol Way to be the state representative for the 133rd District.
The seat was vacated by Democrat Kim Fawcett, who is running for the 28th state Senate District against Republican Tony Hwang in November.
That Senate seat was vacated by John McKinney, who was also on the Tuesday ballot seeking the Republican vote to be the nominee for governor in the November election.
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