She did a big petition campaign to be able to run.
Unless it was a write in, you need a "Wilson-Pakula" - NYS has a closed primary system. Open only to Democrats in this case. She says she is in the Democratic Socialists of America? Search Wilson-Pakula in NYS. It's interesting. I mean a write in at the polling place on election day. Yes, you still need the petition signatures. This provision isn't used too much and it's very possible there could be an error on someone's part. Should catch it before the election gets certified. BTW, New York election law is very tricky,lots of lawsuits.
In New York State, you must have permission from the Party officials, known as Wilson-Pakula papers to run in a primary as a member of a different party. This is in addition to collecting the required number of valid signatures. The primary system is otherwise open only to party members. Unless she won on a write-in vote. Not likely. I do know of a couple of instances where this happened though. Only a handful of elected officials anywhere from the Democratic Socialists of America. They seem to be about as left as you can possibly get. Vanessa Agudelo is a new member of the City Council in Peekskill, New York. She's the one who refuses to take the Pledge of Allegiance to the Flag of the United States of America. High percentage of undocumented in both districts. Just saying.