Plurality voting: The system used by most political elections, where voters choose only one candidate and the candidate with the highest number of votes wins the election. Using this system, Smith wins the election with 6 million votes.
Ranked choice: The system that is used in Australia, Ireland, and, with recent controversy, in Maine’s 2018 state elections, where voters rank candidates in order of their preference. If no candidates have more than 50 percent of first-place votes, the candidate with the least number of first-place votes is removed from consideration, and their votes go to the candidate whom that group listed as their second choice.
Using this system, since Smith’s 6 million votes only account for 40 percent of the total electorate, the candidate in last place, Jones, is removed from consideration and his 4 million votes all go to Davis. This gives Davis 9 million votes, or 60 percent of the total, and the election.
Borda count: A version of the ranked choice system that assigns a pre-determined number of points based on how the candidate is ranked. With a Borda 3,2,1, count system, for example, the first-place candidate gets 3 points per vote, second place gets 2 points per vote, and third place 1 point per vote.
Using this system, Jones has the highest number of points and wins the election.
Smith: (6 million * 3) + (5 million *1) + (4 million *1) = 27 million points
Davis: (5 million *3) + (4 million * 2) + (6 million *1) = 29 million points
Jones: (4 million * 3) + (6 million * 2) + (5 million * 2) = 34 million points
