In politics, a “bellwether” refers to a geographic area whose political beliefs and voting preferences reflect that of a wider area.
For example, a county might be said to be a “bellwether county” if it consistently votes the same way as the majority of the state. A state is considered a “bellwether state” if it usually votes the same way as a majority of the country.
According to Merriam-Webster, the term is derived from the Middle Ages:
Long ago, it was common practice for shepherds to hang a bell around the neck of one sheep in their flock, thereby designating it the lead sheep. This animal was called the bellwether, a word formed by a combination of the Middle English words belle (meaning “bell”) and wether (a noun that refers to a male sheep that has been castrated).
One famous example of a specific bellwether in politics is known as the “Missouri Bellwether,” in which the state of Missouri has voted for the presidential winner in every election from 1904 to 2016. This phenomenon is explained in a 2016 article from The American Conservative.
Political scientists spend a great deal of time analyzing bellwethers to try to discern voting patterns and political affiliations. But as pointed out by NPR in 2008, true bellwethers are becoming harder and harder to come by as demographics change on both local and state levels: “Every election season, reporters fan out to states and counties that claim to be political bellwethers. After all, if the voters in these places have been right in the past, maybe they’ll be right again. But in presidential politics, there are actually few true bellwethers left.”
An example is the state of Ohio, which was also long considered a bellwether for national voting preferences, but started losing its status as a bellwether as the state started more conservative, as noted by the New York Times in 2016.
A Michigan State University academic paper points out that the concept of a bellwether itself is not held with as much regard as it used to be:
Bellwethers aren’t traditionally embraced by political science. But that is because the concept is traditionally measured in very poor way. Counties are termed bellwethers based on a history of coincidence wherein a county has picked the winner of the state or country for the last X elections and what defines a successful county pick is a very arbitrary 50% cutoff.
To make the concept of a bellwether more precise and accurate, political scientists have identified three types of bellwethers:
- All-or-Nothing Bellwethers: these bellwethers are states or counties that have chosen the national presidential winners with a great deal of accuracy, such as Missouri, Ohio and New Mexico.
- Barometric Bellwethers: these bellwethers are ones that best reflect the national vote percentage.
- Swingometric Bellwethers: these bellwethers are counties or states that directly reflect the swing in voting on a national level, and tend to vote differently depending on the specific candidate or issue.
A related term in politics is “battleground.”