Mayor Thomas M. Menino has a history of playing hard to get with Democrats running for statewide office, and he has proved in the past that personality can trump political party. Menino has stated almost unequivocally that he will not break from his party and back Republican Senator Scott Brown’s reelection bid. But Menino has been coy enough about an endorsement of Democrat Elizabeth Warren - smiling slightly as he gives a noncommittal answer - that people keep asking the question. The real issue is whether Menino will push his get-out-the-vote machine for Warren in November, and if it actually matters in a presidential election year when a surge of voters can double the number of ballots cast in Boston.