Unofficially, Tubiolo garnered 2,129 votes to Peters' 1,288.
Tubiolo takes over for fellow Republican Bernice Spreckman, who resigned in June. Tubiolo had served as a legislative aide under Spreckman for five years.
District 17 is made up of East Yonkers, Fleetwood and Mount Vernon West.
Tubiolo was accompanied by Westchester County Executive Rob Astorino when he cast his vote Tuesday. Spreckman also endorsed Tubiolo.
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