The first-past-the-post electoral system is a voting system for single-member districts, variously called first-past-the-post (FPTP or FPP), winner-take-all, plurality voting, or relative majority. In political science, it is known as Single-Member District Plurality or SMDP. This system is in use at all levels of politics; it is very common in former British colonies. For a thorough list, see below.
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2 An example 3 Potential for tactical voting 4 Where it's used 5 External links |
Each voter selects one candidate. All votes are counted and the candidate or option with the most votes is the winner.
Imagine an election to choose the capital of Tennessee, a state in the United States that is over 500 miles east-to-west, and only 110 miles north-to-south. Let's say the candidates for the capital are Memphis (on the far west end), Nashville (in the center), Chattanooga (129 miles southeast of Nashville), and Knoxville (on the far east side, 114 northeast of Chattanooga). Here's the population breakdown by metro area (surrounding county):
Procedures
An example
Let's say that in the vote, the voters vote based on geographic proximity. Assuming that the population distribution of the rest of Tennesee follows from those population centers, one could easily envision an election where the percentages of sincere preferences would be as follows:
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42% of voters (close to Memphis) 1. Memphis 2. Nashville 3. Chattanooga 4. Knoxville |
26% of voters (close to Nashville) 1. Nashville 2. Chattanooga 3. Knoxville 4. Memphis |
15% of voters (close to Chattanooga) 1. Chattanooga 2. Knoxville 3. Nashville 4. Memphis |
17% of voters (close to Knoxville) 1. Knoxville 2. Chattanooga 3. Nashville 4. Memphis |
If voting follows sincere preferences, Memphis is selected with the most votes. Note that this system does not require that the winner have a majority, but only a plurality. That is, Memphis wins because it has the most votes, even though more than half of the voters preferred another option.
First-past-the-post encourages the tactical voting technique known as "compromising": voters are encouraged to vote for one of the two options most likely to win, even if it is not their most preferred option. In the above example, voters from Chattanooga and Knoxville may "compromise" by voting for Nashville, which they prefer to Memphis.
If enough voters vote using this tactic, the first-past-the-post system becomes a form of runoff voting where the first round is held in the court of public opinion.
Because of these anomalies and the tactical-voting tendencies, Duverger's law predicts that constituencies that use first-past-the-post systems will become two-party systems.
Countries that use this system to elect the lower or only house of their legislature:
Bahamas -- Bangladesh -- Barbados -- Belize -- Botswana -- Canada -- Dominica -- The Gambia -- Grenada -- Jamaica -- Federated States of Micronesia -- Nepal -- Papua New Guinea -- Saint Kitts and Nevis -- Saint Lucia -- Saint Vincent and the Grenadines -- Samoa -- Solomon Islands -- Trinidad and Tobago -- United Kingdom (Westminster elections) -- United States -- Zambia
Source: Making Votes Count, Gary Cox (1997)
Potential for tactical voting
Anomalous results
An interesting anomaly in the results of this system arose in the Canadian federal election of 1926 for the province of Manitoba. The province was entitled to 17 seats in that election. The percentage of votes received across the province were
The apportionment of seats however was
The Conservatives clearly had the largest number of votes across the province, but received no seats at all. The other parties were able to have success by having concentrated support in particular constituencies, and by not running candidates in others.Duverger's law
Where it's used
External links