
Britain's Prime Minister Boris Johnson leaves from a polling station with his dog Dilyn after casting his ballot in London Thursday. Photo: Daniel Leal-Olivas/AFP via Getty Images
Polls across the United Kingdom opened Thursday morning as millions of Brits vote in the country's third general election since 2015.
Why it matters: Prime Minister Boris Johnson has staked his leadership on a promise to "get Brexit done" by securing a majority in the election, after facing a parliamentary impasse on the issue in a minority government. But if he loses, he'll go down as one of the shortest-serving prime ministers in history.










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