One of the most watched races in the Hudson Valley is for the 40th District state Senate seat.

Just because a candidate finished election night with the lead doesn't necessarily mean they'll carry it to victory - it's all coming down to those mail-in ballots, including in the heated fight for the 40th state Senate seat.

That seat covers portions of Westchester, Rockland and Dutchess counties.

Republican Rob Astorino is ahead of first-term Democrat Pete Harckham, but there are tens of thousands of absentee ballots that still have to be counted.

The numbers could still fluctuate because under New York law, absentee ballots can be received up to a week after the election, as long as they are postmarked by Election Day.

This would mean that ballots could arrive to the Board of Elections as late as Nov. 10.

Republican challenger former Westchester County Executive Rob Astorino is leading the Democratic incumbent New York state Sen. Pete Harckham.

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This will likely drag out the race for days or maybe even weeks.

Sen. Harckham was feeling optimistic Wednesday that a victory is within reach.

Astorino, the former two-term Westchester County executive and former candidate for governor, came into the race with a lot of name recognition and plenty of cash to spend. He positioned himself as a law-and-order candidate, intent on repealing New York's controversial bail reform law, highly unpopular with many local voters in a district traditionally held by Republicans, despite a Democratic enrollment advantage.

The Republican Party is hoping to gain some ground after a bruising election night two years ago.

While the Senate Democrats fight to inch closer to a two-thirds, veto-proof supermajority, right now they are only a handful of votes shy, which is part of what makes this local race such high stakes.