(Bloomberg) -- Boris Johnson suffered a major upset as his Conservative Party lost a key Parliament seat in southwest England, raising fresh questions about his leadership and faltering popularity in traditional Tory heartlands.

The Liberal Democrats, typically regarded as the third party of English politics, overturned a huge Conservative majority to take Tiverton and Honiton, a rural constituency held by the Tories since its creation in 1997.

Johnson’s Coalition Is Crumbling Among New Tory Voters and Old

The result will renew doubts over Johnson’s future, just over two weeks after four in 10 Conservative Members of Parliament voted to oust him as leader. The prime minister has faced intense pressure for months over a series of scandals related to his conduct in office, including being fined by police as part of a probe into illegal parties held in Downing Street during the pandemic.

With support for Johnson’s Tories slumping nationwide amid a cost-of-living crisis, rebels in his party have pointed to a series of potential hurdles -- including the Tiverton and Honiton by-election -- as moments that could again galvanize efforts to remove him.

The collapse in support in the Devon seat is especially troubling for Tory strategists as they look forward to the next general election, which must be held by January 2025.

Johnson steered his party to its biggest national win in more than three decades in 2019, by convincing Labour voters in the opposition party’s so-called Red Wall in northern England to back his pledge to “get Brexit done.”

But Tory MPs in southern England fear Johnson has since focused too much on the north, and risks taking the commuter belts and countryside of the south -- areas that have long been considered Conservative -- for granted.

The Tories had already lost two seats to the Liberal Democrats since 2019, and the party’s momentum is a direct threat to some prominent Tories including Deputy Prime Minister Dominic Raab.

The special election in Tiverton and Honiton was triggered when Conservative MP Neil Parish resigned, after he acknowledged he had watched pornography twice in Parliament. He had represented the seat for 12 years and was returned with a massive majority of over 24,000 in 2019.

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