The New York Times has a good explainer, with good visualization aids, that explains how RCV will work in our June primaries for mayor. I wanted to clarify one point of potential confusion.
The story says:
In New York’s primary, these rounds of elimination will continue until there are two candidates left — even if a candidate collects more than 50 percent of votes before the very end. In each round, when a candidate gets eliminated, his or her votes get redistributed to whoever was ranked next on the ballot.
A reader might think, wait a minute, once someone has gotten more than 50 percent of the votes, haven’t they won? Why is there still further counting to be done?
The answer is yes, once a candidate has more than 50 percent, that candidate has indeed won. Nothing in later rounds of counting could change that outcome. The reason the counting still continues is purely for informational purposes, so that the public can see how the process plays out all the way until there are only two candidates remaining and no more votes to be redistributed.
This is an approach a number of jurisdictions use with RCV, as Michael Parsons and I explain in our article on RCV.