Yesterday’s mayoral primary in New York City was run by ranked choice voting (as I suspect anyone who comes to this site has heard). Analysis of preference flows, when they are available, is going to be interesting. Actually, because it was a highly competitive primary for determining the Democratic nominee, there may not be much discernible pattern. That is, unlike a general election with multiple parties (as in Australian House elations, for example), voters may have had little information or understanding of how to use their ranked choices effectively. This will have been complicated further by what I understand was a relative paucity of explicit preference-exchange deals among candidates (e.g., “vote for me 1st, and then give your second choice to X”). In a primary for a single office, there may not be much incentive for candidates to do such deals. There is little to trade–or at least limited credibility to such trades–unlike in a general election, particularly a partisan one that spans across multiple districts. (There were, of course, also primaries for City Council seats; it is not clear to me how preference trades might work between a mayoral primary and council primaries. Again, the lack of party alignments of the candidates–or, rather, all being of the same party–probably greatly limits effectiveness of any such deals.)
From what we know so far, on first-choice votes, the leading candidate has under a third of the vote, and the next two are in the 20–22% range. That means a healthy lead for the one in the initial first place, Eric Adams, but also a big shortfall from majority.
I have not followed the campaign closely enough to have anything to say about how second preference might break. But I am sure some readers have, so please enlighten us!