The board of elections said nearly 17,000 people voted across the five boroughs Saturday.
There are 104 early voting polling sites.
Some of the candidates themselves voted on the first day.
Kathryn Garcia and Shaun Donovan cast their votes in Park Slope and Andrew Yang accompanied his wife as she cast her vote at John Jay College.
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Voters can choose only one candidate, or to rank up to five candidates, in order of preference.
"Ripping the band-aid off. I've seen so many of the commercials, just wanted to have my voice heard as soon as the polls opened and just get it out of the way," voter Mattie Quinn said.
People have from now until June 20 to cast their votes early.
Voters will want to check ahead at their local polling place because the hours vary, but New Yorkers might want the extra time to think about their vote this year.
The City's Board Of Elections website now has a wait time map for early voting locations. Find one by typing in your address.
Find your local polling place
Polls will be open at various times through next weekend:
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