Every voting system is a machine. It takes individual preferences as inputs and produces a winner as output. Change the machine, and you change who wins — sometimes without changing a single voter's actual opinion. This lesson is about one specific proposed upgrade to that machine: ranked-choice voting. And whether it actually does what its supporters claim.

In a standard plurality election, you pick one candidate. Most votes wins. Simple. But this creates a brutal trap called the spoiler effect. In 2000, Ralph Nader won 97,000 votes in Florida. George W. Bush beat Al Gore by 537. Exit polls suggested most Nader voters preferred Gore as their second choice. Whether Nader 'cost' Gore the election is debated — but the structure of the problem is real. Voting for who you actually want can hand victory to who you least want. So voters lie. They vote strategically, not honestly. Ranked-choice voting (RCV) tries to break this trap. Instead of marking one candidate, you rank them: 1st choice, 2nd choice, 3rd choice. If your top pick can't win, your vote doesn't die — it transfers to your second pick. The machine counts your honest preference without punishing you for having one.

The counting works in rounds. After the first round, if no candidate has a majority, the last-place candidate is eliminated. Everyone who ranked that candidate first has their vote transferred to whoever they ranked second. Repeat until someone crosses 50%. The winner doesn't just need the most votes — they need to be broadly acceptable to a majority of voters, including people whose first choice lost.