Overall, Cuomo got 68% of the vote in New York City. Teachout needed to flip that number pretty significantly in order to win, which I hope was the goal of the campaign. (Should be the goal of any political campaign.) But she did win a few Assembly districts and was competitive in a few others.

Her best district was Brooklyn's 52nd, where she received about 67% of the vote:

As you can see, this district includes Brooklyn Heights, Cobble Hill, parts of Park Slope, DUMBO, and other very high income areas. In fact, a very healthy portion of your Wall Street professional class workforce lives in this district. There are broad sections of this district that are almost exclusively white. I'm glad she won this district, but this isn't the sort of place that has to be your base vote if you plan to win a Democratic Primary against a strong incumbent.

Teachout also won the 66th, 67th, and 69th districts in Manhattan.

That's Greenwich Village, Soho, and Tribeca. Really difficult to find a more upscale, richer part of town. Yes, that dot you see there is in fact Goldman Sachs headquarters.
Teachout also won Chelsea and other parts of the West Side of Manhattan. Once again, predominantly white and high income.
She also won the Upper West Side, but by a slimmer yet still robust margin. But same demographic profile as the other districts.

You'll also notice these districts all have substantial private, expensive university presences in the case of Columbia and NYU.

Now, lets look at where she lost big:

This is East Flatbush and parts of Canarsie. It is a community I know very well as I have many relatives and friends here. It is heavily Black, the majority of whom have their roots in the islands of the Caribbean and South America. Teachout got clobbered here, losing 88 to 10. It is a very working class neighborhood with a great deal of poor mixed in. A populist candidate running against Governor 1% shouldn't get beat here unless there is something wrong.
This is the Soundview section of The Bronx. It is a heavily Latino district, very working class with some poor mixed in. Teachout got blown away in this neighborhood 89 to 9. In the heavily middle class Jewish section of the Bronx, same story. Teachout was blown away by huge margins.
In predominantly Asian Flushing, in Queens, same thing. Wasn't even close. A blowout.

You can look at the Italian sections of the Bronx, Irish sections of Queens, Middle Eastern sections of Brooklyn, you'll find the same thing. She lost Polish Greenpoint and Russian Brighton Beach. These middle income and poor neighborhoods were ripe for the taking against Governor Rich People, but that didn't happen. Instead, Teachout did all of her winning among high income white liberals. That's not how you build a populist victory. Worse, she lost her own district in newly gentrified Fort Greene. Also by a large margin.

The lesson to be learned here for liberals and Kossacks is that one has to know where one's base is and you're not going to find it by looking in the mirror. Zephyr Teachout did not have the kind of money it would take to make a credible challenge, but she did manage to win some districts. So she did get known, she just didn't get known where it mattered most. Nor did she have the kind of personal profile or candidate skills to build up a real grassroots movement with populist appeal. She was absolutely uncompetitive in all the places where one needs a populist message to be appealing.

Don't ask fellow liberals who most appeals to your vote. Ask those folks in those neighborhoods who would be a good fit to win their votes. That's the way you build a campaign for victory. Otherwise, people are going to go with the devil they know. If you're going to unseat an Democratic incumbent via populist primary challenge, the most important thing to know is where the 99% base actually is rather than where you think it is.