Bellwether constituency

A bellwether is one that leads or indicates trends; a trendsetter.

The term is derived from the Middle English bellewether and refers to the practice of placing a bell around the neck of a castrated ram (a wether) leading his flock of sheep. The movements of the flock could be noted by hearing the bell before the flock was in sight.

In politics, the term is more often applied in the passive sense to describe a geographic region where political tendencies match in microcosm those of a wider area, such that the result of an election in the former region might predict the eventual result in the latter. In a Westminster-style election, for example, a constituency, the control of which tends frequently to change, can mirror in its popular vote the result on a national scale.

In Australian federal elections, the electoral division of Eden-Monaro in New South Wales elected its Member of Parliament from the party which won government at every federal election from 1972 until 2016, when the record was broken after Labor won the seat, while the Coalition won government. Following this, the Division of Robertson in NSW became the nation's new longest-running bellwether seat, continually won by party that also won government since the 1983 election. The Division of Lindsay in NSW, has elected its Member of Parliament from the party which won government in every Federal election since its creation in 1984. Both Lindsay and Eden-Monaro lost their bellwether status in the 2016 election, both electing Labor MPs, despite a narrow Coalition win nationwide. The Division of Makin in South Australia was a bellwether division from 1984 until 2010, although ceased its bellwether record in 2013, when Makin stayed Labor as the Coalition regained power nationwide. Also, in terms of nationwide two party preferred vote, Eden-Monaro, Lindsay, Robertson and Makin have bucked the bellwether trend in the past by voting Liberal at the 1998 federal election. In purely statistical terms, the state of New South Wales, which has the largest population of any Australian state or territory, could also be considered a "bellwether", as, until the 2016 federal election the party which wins government has won the majority of House of Representatives seats in that state at every election since 1963. Unlike many bellwethers, these are cited by analysts solely for their record and are not usually attributed to demographic factors that reflect the median of Australia.

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