The 28th District includes Easton, Fairfield, Newtown and parts of Weston and Westport.
McKinney is not seeking re-election and is running instead for the Republican nomination for governor.
Fawcett served four terms as a State Representative for Fairfield’s 133rd district starting in 2006.
"I am honored to accept this nomination and promise you that I will be out knocking on doors and working my hardest to become the first woman ever to represent the 28th District, and the first Democrat to hold this Senate seat in 40 years," said Fawcett.
Fawcett also promised to continue her work as an independent, results-oriented leader focused on fiscal responsibility, building relationships and serving the needs of her voters.
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