Single Choice Voting
Single choice voting (SCV) is the most common voting method used in United States elections. A voter selects only one candidate for an office. The criteria to determine a winner can be either plurality - the candidate who acquires the most votes - or majority - the candidate who acquires a majority of the total votes cast. For a majority criteria SCV if no candidate satisfies the criteria the two top vote getters may compete in a runoff election or the winner may be selected by the state legislature. Plurality SCV is popular because it is simple to implement, it minimizes the time to vote and does not require further voting action unless there is a tie vote. Some disadvantages of SCV are that it promotes the evolution of a two major party contest and third party and independent candidates participate as spoilers as explained in the following video.
Ranked Choice Voting
Ranked choice voting (RCV) is also known as instant runoff voting (IRV) first implemented statewide by Maine and recently approved in Alaska. A voter identifies first, second, third, etc. choice candidates for an office. If the candidate with the most first choice votes did not receive a majority of the total votes cast then the candidate with the least number of first choice votes is eliminated. Then the second choices of the voters for the eliminated candidate are assigned to the remaining candidates. The process continues until a candidate has received a majority of the total votes cast and is declared the winner. Two disadvantages of ranked choice voting are increased complexity and time for voting and computing the results. One advantage is the elimination of the spoiler impact in single choice voting when a voter selects a preferred but unlikely to win candidate. Another advantage is the assurance of the winning candidate receiving a favorable vote from a majority of the voters in the final round eliminating the need for a runoff election as explained in the following video.