The city's 33,000 union transit workers, one month to the day after they stranded 7 million riders with a crippling three-day strike, voted Friday to reject their new three-year contract.The workers, by a seven-vote margin out of more than 22,000 votes cast, opted to reject Transport Workers Union local president Roger Toussaint's call for ratification and follow the lead of a dissident group urging rejection. The voting ended at noon Friday.