With 42 out of 43 districts reporting, Diana defeated Democrat Robert Giordano 55 percent to 45 percent and Bernard defeated Roseanne Brackett 59 percent to 41 percent.
The election gives the Republicans a 3-2 majority on the town board.
Diana lost last year to trustee Susan Siegel. In 2013 he was defeated by Dave Paganelli in the race for highway superintendent. Bernard previously served on the town board.
Bernard will fill the remainder of current State Senator Terrence Murphy's unexpired term while Diana will serve the remainder of former councilman Nick Bianco's term.
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