Single-winner voting systems

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Single-winner voting systems are voting systems in which a predetermined constituency elects a single person to some office; they contrast generally with proportional representation, in which constituencies are combined to elect several representatives at once.

If there is to be only one officeholder - often the case for executive positions, such as president, mayor, or governor - single winner systems are the only option. If there are various officeholders - for instance, for a legislature - there are other voting systems available.

Some examples of single winner systems are: Plurality, Runoff voting, IRV, Approval voting, Range voting, Borda count, Minimax, Schulze, and Ranked Pairs. Of these, Plurality and Runoff voting are the most commonly used in conjunction with single-seat constituencies, and their advantages and disadvantages are often conflated with the advantages and disadvantages listed below.

[edit] Advantages

[edit] Each representative must be a winner

Sometimes, the voters are in favour of a political party, but do not like specific candidates. An example was the premier of Alberta, Don Getty. His government was re-elected in 1989, but because of voter dissatisfaction with the way the government was led, Getty, the leader of the Alberta Progressive Conservative Party, was not re-elected by voters from his electoral district.

However this can also have the opposite effect. A candidate who is very popular among the electorate in general may lose if the candidate or the candidate's party is unpopular or has caused dissatisfaction in his or her seat. An example was how Winston Churchill lost the 1945 UK Parliamentary elections. Churchill had over a 90% approval rating, but the Labour Party won overall defeating Churchill's Conservative Party and making Clement Attlee the Prime Minister.

Similarly, in the 1999 Ontario provincial election, Mike Harris and his Progressive Conservative party was re-elected to a majority government, but symbolic of the growing discontent among voters about cuts to education, his education minister and strong ally was resoundingly defeated by the opposition candidate.

It is often claimed that because each electoral district votes for its own representative, the elected candidate is held accountable to his own voters, thereby helping to prevent incompetent, fraudulent or corrupt behavior by elected candidates. The voters in the electoral district can easily replace him since they have full power over who they want to represent them. In the absence of effective recall legislation, however, the electors must wait until the end of the representative's term. Moreover, it is possible for a winning candidate or government to increase support from one election to the next, but lose the election, or vice-versa. Also, it is generally possible for candidates to be elected if the party regards them as important even if they are fairly unpopular, by moving the candidate to a safe seat which the party is unlikely to lose or by getting a candidate in a safe seat to step down.

On the flip side, in a constituency system, a candidate who is popular nationally may be removed if he is unpopular in his own district. This feature, however, is also present in every proportional system in existence other than a closed party list.

[edit] Regionalism

FPTP also encourages regional parties which can be very popular in one geographical region but have little or no support in other parts of the electorate.

Some parts of a given country may have local support for a specific political party which may have no support in another region. In the United States for example, small parties, like the Socialist parties may have scattered support in certain municipalities, so a candidate from one of there regions may appear on the ballot there, whereas his name would not appear on the ballot in a region where the party has little support.

A good example of this is Canada, where, in 1993, the separatist Bloc Québécois formed the opposition, despite getting only 13% of the vote. In the 2006 election, the Bloc Québécois received 51 seats (16.6% of the total seats) with 10.5% of the total votes. In contrast, the New Democratic Party received 29 seats (9.4% of the total seats) with 17.5% of the total votes.

[edit] Does not give parties excessive power over politicians and voters

This is actually a disadvantage of party list systems, one alternative to single-winner systems. Such systems force voters to vote by party rather than by candidate, giving the party structure the power of a middleman.

[edit] Disadvantages

[edit] Effect on representation

Created by an organisation promoting proportional representation, this campaign postcard illustrates that Labour obtained a majority in Parliament despite winning only 35.2% of the national vote in the 2005 election.

The most commonly expressed disadvantage — perhaps because it is easiest to express and explain — of first-past-the-post is that the winners of the election may not precisely reflect the distribution of votes, with substantial minority vote blocs ignored in their entirety, to the advantage of plurality winners. Thus, substantial bodies of opinion can be rendered irrelevant to the final outcome, and a party can obtain a majority of seats without a majority of the vote. Examples include the recent United Kingdom general election of 2005 where the new government won a majority of the seats with less than 36% of the national vote. The disproportionate nature of this system also means that whole regions may have MPs from only one party. The British Conservatives won large majorities of seats in the 1980s on a minority of votes while almost all the Scottish seats were Labour, Liberal or SNP; this disparity created tremendous dissatisfaction in Scotland.

A further example of disproportionality arose in the Canadian federal election of 1926 for the province of Manitoba. The province was entitled to 17 seats in that election. The result was very different from how people voted.

The Conservatives clearly had the largest number of votes across the province, but received no seats at all.

The usual cause for these disproportionate results is that a party has a large number of votes across the entire territory, but they are spread out across the territory rather than being concentrated in particular constituencies. Parties with less overall support, but where that support is concentrated in particular constituencies, will win plurality in those constituencies over a party with widely distributed support.

This presents a problem because it encourages parties to focus narrowly on the needs and well-being of specific electoral districts where they can be sure to win seats, rather than be sensitive to the sentiments of voters everywhere. A further problem is that the party in power often has the ability to determine where the boundaries of constituencies lie: to secure election results, they may use gerrymandering — that is, redistricting to distort election results by enclosing party voters together in one electoral district. Moreover, it can be demonstrated that even the use of non-partisan districting methods - such as computers - to determine constituency boundaries tends to generate results very similar to those produced by a majority party with the power to gerrymander in its favour.^[1] Conversely, there are cases where there may be no possible way of drawing contiguous boundaries that will allow a minority representation.

It often seems fundamentally unfair that a party should have a substantially greater or lesser share of seats than their share of the vote. A further consequence of the system is that many such elections can be considered won before all votes are tallied, once there are no longer enough uncounted votes to override an established plurality count. Though not necessarily a disadvantage, this can produce a feeling of disenfranchisement among voters when running tallies are reported through the media.

This argument applies to most other single-winner voting systems.

[edit] How the seats can differ hugely from votes

In the FPTP system, the proportion of seats won may differ hugely from the proportion of votes received. A huge disparity between votes and seats is demonstrated below.

In the first table labour has rightly won, but the size of its victory is unjusitified by votes. Also, the LibDems have won a seat with half the Conservative vote when the Conservatives have no seats!

[edit] How polarisation can stop seats changing hands

If a country becomes polarised, many constituencies will have strong majorities in certain seats. This will mean that marginal seats could be few and far between, making it hard for many seats to change hands when a party's vote drops.

Below are two tables of the six most marginal seats in a country. They both show the same seats but the second table is more polarised. Both show what would happen when there is a 5 per cent swing from Cons. to Labour. Amongst the non-polarised seats, Labour would make a larger gain than it would with polarised seats.

[edit] Safe seats

See also: Rotten borough

A safe seat is one in which a plurality of voters support a particular candidate or party so strongly that their votes for that candidate are guaranteed in advance of the election. This causes the difficulty that all other voters in the constituency can then make no difference to the result, since the winner of the seat is already known in advance. This results in serious feelings of disenfranchisement, and to abstention.

As an example Gerry Adams of Sinn Féin holds the 4th safest parliamentary seat in Westminster for his West Belfast constituency.

[edit] Wasted Votes

Wasted votes are votes cast for losing candidates or votes cast for winning candidates in excess of the number required for victory. For example, in the UK General Election of 2005, 52% of votes were cast for losing candidates and 18% were excess votes - a total of 70% wasted votes. This is perhaps the most fundamental criticism of single-winner systems when used for a legislature, that a large majority of votes may play no part in determining the outcome. Proportional representation systems attempt to ensure that almost all votes are effective in influencing the result and the number of wasted votes is consequently minimised.

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[edit] Wipeout and clean sweep results

Since single member constituencies generate a winner's bonus, if not a winner-takes-all situation, the opposition can be left with few if any seats (see above).

It is argued that a weak or absent opposition due to an electoral wipeout is bad for the government. Provincial elections in several Canadian provinces provide suitable examples.