Each constituency is represented by a member of parliament, or MP. A vote takes place in every constituency where each citizen chooses one candidate to represent them in parliament.
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Any British, Irish or qualifying Commonwealth citizen who resides in the U.K. and over 18 is able to vote.
“Postal votes are possible for citizens who reside abroad but who have been on the electoral register any time in the previous 15 years,” Watt said. “This time last year, the total number who fell into that category was approximately 46 million people.”
Despite the number of political parties, only the Labour and Conservative parties have been the winners of modern British elections.
“While some of these smaller parties will win individual seats, they will not win enough across the nation to form a government,” Watt said. “In order to govern with a majority, one single party must win 326 seats or more. The larger the majority, the easier, in theory, it is for the government to pass legislation.”
All 650 seats in the House of Commons are up for grabs in the election — Britain’s first December vote since 1923 — which is being held more than two years early in a bid to break the country’s political impasse over Brexit.
“In some elections in the past, some smaller parties have performed much better than expectations,” Watt said. “In 2010, the Liberal Democrats secured 59 seats across the U.K., after which they were part of a coalition government with the Conservatives.”
If no single party secures the 326-plus seats, the party with the largest numbers governs with a minority.