First-past-the-post is a voting system used by some countries to elect their governments or the members of their parliaments. In a first-past-the-post system, a country is divided into constituencies. In these constituencies people known as candidates, each of whom usually represents a different political party, will stand for election to the country's parliament. In the individual constituencies, the candidate who gets the most votes from people, wins the race to be elected to a seat in parliament. Plurality is another name for such an electoral system. It is in contrast to the majority system, where the winning candidate must have more votes than all other candidates combined.
If a party wins over 50% of the seats, it can form a majority government. If no single party wins over 50% of the seats, then either the party with the most seats can form a minority government, or a coalition government can be formed from two or more of the other political parties who together have over 50% of the seats.
First-past-the-post, often called 'plurality voting', is the most common method for electing representatives in the United States and some other countries. Voters vote for one candidate, and the candidate with the most votes wins.
Political parties often use a primary in order to avoid splitting their party vote in a general election. For example, if 60% of the voters are Republican, and 40% Democrat, but two Republicans run for the same office and each get 30% of the vote, the Democrat would win with 40%, since that is the most votes, even if 60% of voters least preferred the Democrat.
If more than two candidates are on the general election ballot, voters often compromise vote an acceptable candidate whom they think has a chance of winning.
Opponents of plurality voting argue that the media has too much power since they tell people which of the two has a chance and that voting for a third candidate is in effect voting for the worse of the two strong candidates. It is theoretically possible that the two "front runner" candidates not to be not centrist and not to represent the people.
Proponents of plurality voting argue that it is very simple and that it forces voters to elect a centrist candidate through compromise voting. To avoid its problems, some elections require a minimum percentage of votes, or a majority, through a "run-off election".
In a first-past-the-post system, candidate A wins because that candidate received more votes than anyone else.