Winner-Take-All System

IN A WINNER-TAKE-ALL system, the goal of an election is to pick a winner, and the winner takes all. This is in contrast to proportional representation, where the goal is to choose a legislature that will mirror the preferences of voters as closely as possible. There are several kinds of winner-take-all systems, and a key distinction can be made between plurality and majority formulas. Among countries using winner-take-all formulas for legislative elections, single-member district plurality is by far the most widely used (in 54 cases out of 91 studied). This system is used for legislative elections in countries such as Britain and former British colonies such as the United States or India. In this case, the candidate who receives the largest number of votes wins the election.

If a majority is needed to win an election, the requirement can be met in either of two ways. The first possibility is the system used in France for presidential elections (and, in a slightly modified form, for electing the French parliament). To be elected, a candidate must win a majority (at least 50 percent plus one of the total votes cast). If no candidate wins a majority, a runoff election is held between the top two vote getters, which ensures that the winner of the second round is elected with a majority of votes. About 30 countries, mostly former French colonies and former Soviet republics, use this system, known as the two-round system or majority-runoff, for their legislative elections. An even larger number of countries, approximately 50, hold their presidential elections under such system. This system is also used in Louisiana.

The second possibility to ensure a majority for the winner, while avoiding the need for a second round, is the alternative vote (also known as preferential voting). This system is used in Australia for legislative elections and in Ireland for presidential elections. Instead of choosing just one candidate, each voter ranks candidates: first choice, second choice, third choice, and so on. If no candidate gets a majority of first preferences, the candidate with the lowest number of first preferences is eliminated, and voters' second preferences are counted from the ballots on which that candidate was ranked first; the process continues until one candidate gets a majority of votes.

For example, in a district in which a Republican, a Democrat, and a Green candidate are running, if 100,000 voters cast a ballot, and the results (first preferences) are: 48,000 votes for the Republican candidate, 47,000 votes for the Democratic candidate, and 5,000 votes for the Green candidate, no candidate received a majority of first preferences. The Green candidate, who received the lowest number of first preferences, is eliminated. The next step is to look at the second preferences on the 5,000 ballots on which the Green candidate was marked as the first preference. If, for instance, the Democratic candidate appears as the second choice of 4,000 of Green voters, and the Republican candidate is the second preference of only 1,000 of Green voters, the total vote of the Democratic candidate becomes 51,000, and he or she is elected, despite being in the second position after the first count.

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