Newcomer David Pollak was elected to the School Committee along with incumbents Helen Charlupski and Susan Wolf Ditkoff in the town election Tuesday. Ditkoff received 4,992 votes to top the ticket in the race for the three seats. Charlupski received 4,544 votes, and Pollak secured the third seat with 4,292 votes, while challenger Laurence Onie finished fourth with 1,606 votes, according to unofficial results from the town clerk’s office. In an uncontested race, Neil Wishinsky was elected to the Board of Selectmen; the seat had been held by Jesse Mermell, who stepped down in January to take a job with the Patrick administration. In a five-way race for four seats as Public Library of Brookline trustees, newcomer Puja P. Mehta, with 4,142 votes, joined incumbents Michael A. Burstein (4,343), Jennifer Rees (4,274), and Judith A. Vanderkay (3,873) in winning election to the board. Challenger Magdalene Moran received 2,381 votes. The results of the election are posted on the town’s website, www.brooklinema.gov. In the special US Senate primary on Tuesday, US Representative Edward Markey far outpaced fellow Democratic congressman Stephen Lynch among local voters and statewide; in Brookline, the tally was 6,851 to 916 . In the Republican Primary, statewide winner Gabriel E. Gomez received the most votes in Brookline with 439, compared with 252 for Michael Sullivan and Daniel Winslow’s 175 votes.