We will need to wait to see the cast vote records from the primary (they were available last time, so presumably—and hopefully—they will be again this time), but it’s conceivable that Mamdani was not the Condorcet Winner. In an election that was as polarized as this one appeared to be from media reports of the campaign—with Cuomo and Mamdani at opposite ends of the divide, and with Mamdani not clearing 50% of the first-choice votes, what matters for a Condorcet-based analysis is what were the lower-ranked choices of Cuomo supporters. If enough of them they ranked Brad Lander and/or Adrienne Adams higher than Mamdani, it’s possible that either Lander or Adams (or both) would beat Mamdani head-to-head (which is what’s relevant for a Condorcet analysis). Likewise, if enough Mamdani supporters ranked Lander and/or Adams higher than Cuomo, Lander and Adams might emerge as the Condorcet Winner based on an analysis of all the head-to-head matchups from the ranked-choice ballots. 

As the Democratic Party—and the nation more broadly—endeavors to determine what should be the major lessons from this primary election, it’s possible that one lesson might end up being that the will of the electorate (and thus in this case the will of the political party in selecting its nominee for the general election) would have been better served by using a Condorcet-based tabulation of the ranked-choice ballots, rather than the “instant runoff” method that tends to elect one of the two most polarizing candidates in an election.

For more on a comparison between the “instant runoff” and Condorcet versions of RCV in the context of polarization, see the law review article I co-authored with Nate Atkinson and Scott Ganz and chapter two of the book I co-edited with Larry Diamond and Rick Pildes.