proportional representation Proportional representation (PR) refers to a type of electoral system under which subgroups of an electorate are reflected proportionately in the elected body. The concept applies mainly to geographical (e.g. states, regions) and political divis ...

(PR)

electoral system An electoral system or voting system is a set of rules that determine how elections and referendums are conducted and how their results are determined. Electoral systems are used in politics to elect governments, while non-political elections ma ...

s, an underhang seat is a seat that becomes vacant because the party that was entitled to it by virtue of its share of the total votes cast was unable to fill it through having submitted too few candidates. Under

party-list proportional representation Party-list proportional representation (list-PR) is a subset of proportional representation electoral systems in which multiple candidates are elected (e.g., elections to parliament) through their position on an electoral list. They can also be us ...

systems, parties receive a number of seats in proportion to the number of votes they received. If a party does not have enough people to fill its vacancies, there is an underhang. For example, if a party wins enough votes for ten seats, but only has seven people nominated on its list, then there is an underhang of three seats. Parties with underhangs usually are not entitled to retroactively add to their list, and lose the potential seats represented by the underhang. For instance, if New Zealand's 99 MP Party (whose stated manifesto was to reduce the size of parliament) had received five percent of the vote in the

2005 New Zealand general election 5 (five) is a number, numeral and digit. It is the natural number, and cardinal number, following 4 and preceding 6, and is a prime number. It has attained significance throughout history in part because typical humans have five digits on eac ...

, they would have been entitled to six seats within the 120 seat House of Representatives. But because they had just two people on their list, they would have filled only two seats. The House would thus have shrunk by four MPs. Since the party received only 0.03% of the vote, this eventuality was avoided. Another way of dealing with underhangs is to allow the party to nominate people to become MPs. In the Scottish Parliament an underhang seat was caused by the death of

Margo MacDonald Margo Symington MacDonald (''née'' Aitken; 19 April 1943 – 4 April 2014) was a Scottish people, Scottish politician, teacher and Television presenter, broadcaster. She was the Scottish National Party (SNP) Member of Parliament (United Kingdo ...

in 2014. As she was elected as a regional list MSP as an independent (effectively the sole candidate of "the Margo party") her seat was left vacant until the next election. Parties aim to avoid the problem by having a substantially larger list than they would hope to win as seats.

See also