How are votes counted?

Answer

Ballots are counted in "instant runoff rounds" -- see this video explainer -- where contestants receiving the fewest top-choices are eliminated and their supporters' ballots are then counted toward the next choice indicated on each.

This process "consolidates" the voting power of like-minded voters, no matter how many candidates are running, rather than seeing the strength of their votes diluted and divided between multiple similar candidates.

Here's the part that solves the "spoiler candidate" problem:

These rounds repeat until one candidate has the support of more than half of the voters. Because winning requires a broad majority of support, candidates need to earn their opponents' supporters 2nd and 3rd choice votes on the ballot.

Ranked Choice Voting (RCV) is a simple but powerful solution that gives people a stronger voice and more choice when they vote.