The race for New York City mayor has tightened considerably — with ex-Gov. Andrew Cuomo cutting front-runner Zohran Mamdani’s lead in half from a month ago, according to a new poll. Mamdani, the Democratic nominee, now leads Cuomo, running as an independent, just 44% to 34% among the likely Big Apple voters, the Suffolk University survey found.Republican nominee Curtis Sliwa is in third place with 11% support. But Mamdani had a 20-point lead over Cuomo in Suffolk University’s prior poll conducted in September. It’s Suffolk’s first survey since Mayor Eric Adams completely dropped his re-election bid and endorsed Cuomo. Cuomo...