The Long March to 10 p.m.: How the U.K. Exit Poll Is Made
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In the offices of the U.K. Labour Party, there were astonished cheers. At Conservative headquarters, it was as though the air had been sucked out of the room. The moment the exit poll dropped at 10 p.m. on election day in 2017 was the moment Theresa May realized she had spectacularly failed.