NEW YORK (CBSNewYork) — A special election in Westchester could have a profound impact on the city, Long Island and all of New York state as a whole.

Democrats hope to consolidate control in Albany, while Republicans are desperate to hold on to their last bastion of power.

Campaign signs are sprouting and mailboxes are bursting with political advertisements.

Republican Julie Killian and Democrat Shelley Mayer are vying in a special election for the 37th District Senate Seat that sprawls from northern Westchester to the Bronx line.

“It’s a battle – and it’s a battle not just for Westchester, but who controls the state senate,” political analyst Richard Brodsky told CBS2’s Tony Aiello.

While the election is up to the voters, the political balance is also tied to the whims of a man from Brooklyn.

Right now there are 31 Republicans and 30 Democrats in the State Senate, with two vacant seats formerly held by Democrats – but Brooklyn Democrat Simcha Felder voted to put the Republicans in control.

This week Gov. Andrew Cuomo brokered peace between some breakaway Democrats – the so-called “IDC” – and the rest of their caucus.

Felder’s under pressure to rejoin the Democrats if the party wins on Westchester’s special election day on April 24.

“He’s playing this very close to the vest which is a fairly smart move,” said Brodsky.

If Killian wins, Republicans control the senate.

“The last time the Democrats had all three branches of branches of government they raised taxes $14 billion, new taxes and fees,” said Killian. “(They) took money out of Westchester schools, $377 million.”

But Mayer says a host of progressive issues are at stake.

“With a Democratic majority we can move forward on gun violence protection, climate change, the child victims act, women’s health issues,” said Mayer. “They are blocked by the leadership of the senate.”

The campaign mailings are harsh: Mayer accused of being an out-of-touch Albany insider, Killian portrayed as a tool of the NRA.

“Bet on the Democrat but don’t be surprised if the Republican wins,” said Brodsky, looking the demographics of the district. “Then look to see what happens in Brooklyn.”

Brooklyn’s Felder says he’ll announce which side he’ll caucus with after the April 24 special elections, now just three weeks away.

A Bronx senate seat is also on the ballot that day, but is considered an easy win for the Democrats.