Judge Anthony Provenzano administered the oath of office to Pilla, a Democrat elected on March 18. Pilla was joined by his wife, Margoth, at the ceremony in Port Chester Village Hall.
Election Day returns from the Port Chester Village Clerk's Office put Pilla ahead of village Trustee Gene Ceccarelli, a Republican, by 1,213 votes to 1,115 votes.
Pilla was first elected village mayor in 2007 but was defeated in 2013 by Neil Pagano, a Republican who decided not to seek re-election this year.
Port Chester's two mayoral candidates differed the most over whether to build a new municipal center in the village's downtown. Pilla also ran on an independent ballot line called "No Municipal Center."
Ceccarelli, whose name also appeared on the Conservative and Independence lines, supported construction of a new police and court building at the corner of Poningo and Irving streets.
The mayor's seat has a two-year term and pays $12,633 annually.
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