ALBANY - Democrats won a majority in the state Senate on Tuesday, clearing the way for the party to have complete control of New York state government.

The Democratic Party won at least 35 of the Senate's 63 seats as of late Tuesday night, wrestling control from Republicans who have led the chamber for much of the last century.

That majority appeared likely to grow further: At least six races were too close to call or awaiting results as of 11:30 p.m.

The big victory puts Sen. Andrea Stewart-Cousins, D-Yonkers, in line to become the powerful Senate majority leader, who has a major role in crafting budgets and legislation each year at the Capitol.

Stewart-Cousins will be the first woman and first African-American woman to lead a majority conference in the state Legislature.

"I am confident our majority will grow even larger after all results are counted and we will finally give New Yorkers the progressive leadership they have been demanding," Stewart-Cousins said in a statement.

The high-stakes and expensive battle for control of the Senate had the potential to decide the direction of the state Legislature, where many progressive-minded measures — including bills to bolster abortion rights and gun-control laws — had long been blocked by a Republican majority.

Republicans held a slim one-seat majority going into the elections because a Democrat, Sen. Simcha Felder from Brooklyn, sits with the GOP conference.

But Tuesday's results put the chamber firmly in Democratic hands.

Democrats appeared poised to pick up two open seats in the Hudson Valley, where Assemblyman James Skoufis, D-Woodbury, Orange County, won a district vacated by longtime Sen. Bill Larkin, a Republican.

Democrat Jen Metzger also had a lead of 2,700 votes over Republican Ann Rabbitt with 90 percent of precincts reporting in a district now held by Sen. John Bonacic, an Orange County Republican who is retiring.

Peter Harckham, a former Westchester County legislator, had a 3,500-vote lead over incumbent Sen. Terrence Murphy, R-Yorktown, with 75 percent of precincts reporting. He declared victory around 11:40 p.m.

Republicans had expressed confidence they could hold the majority, saying they could provide the final check and balance in state government.

But around 11:30 p.m., Senate Republicans conceded defeat.

Senate Republican Leader John Flanagan of Long Island called the results "disappointing."

"This election is over, but our mission is not," he said in a statement. "Senate Republicans will never stop advocating for the principles we believe in or the agenda that New Yorkers and their families deserve."

With Gov. Andrew Cuomo winning re-election, Democrats will now control the executive chamber and both houses of the Legislature. The party has a wide majority in the 150-seat Assembly.

Democrats want to codify abortion rights into state law and allow undocumented immigrants to receive tuition assistance. They have also pledged to pass election reforms.

Republicans had vowed to limit state spending and look to make the property-tax cap permanent.

As of late last month, the Senate's campaign committees and political action groups had spent more than $11 million in key races, campaign-finance records showed.

Cuomo had a cozy relationship with Senate Republicans since he took office in 2011, but he ramped up his efforts this year to try to help Democrats win the majority — both with help fundraising and campaigning with party candidates.

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