New polling has revealed that the Conservatives face heavy losses in nearly a dozen constituencies in traditionally Tory voting areas.
According to YouGov, if a general election were held today, the Conservatives would lose 11 of their 41 seats in the pro-Brexit voting South West.
Among seats at risk are environment secretary George Eustice's of Cambourne and Redruth, which has a majority of 8,700 (17.3%) - as well as Brexit minister Jacob Rees-Mogg's constituency of North East Somerset, which has a majority of 14,729 (26.2%).
According to current projections, Labour would gain six of the 11 seats, the Liberal Democrats would gain four, and one would go independent.
The polling comes on the day of two key by-elections for Boris Johnson and his party amid waning public popularity.
Tiverton and Honiton, a Tory heartland, is now at risk of slipping to the Liberal Democrats.
The seat currently enjoys around a 24,000 Conservative majority, but a by-election was triggered after the sitting MP Neil Parish was forced to stand down after watching pornography in the House of Commons.
The west Yorkshire constituency of Wakefield is predicted to return to Labour by a landslide after the Tories won the seat in 2019. An election there was triggered after sitting MP Imran Khan was convicted of sexually assaulting a teenager.
The new polling on Brexit-voting South West areas is likely to cause more frustration in the Conservative party due to growing anger with the prime minister's leadership and his unpopularity among the public.
Earlier this month, the prime minister faced a no-confidence vote after being fined by the Metropolitan police for attending a lockdown party, and the Sue Gray Partygate report revealed the extent of illegal activity on Downing Street during lockdown.
While Johnson survived the no confidence vote, 148 Tory MPs still voted to oust him from office.
The latest polling from YouGov on voter intention also finds the Tories continue to trail Labour with 39% of voters indicating they will vote Labour and 33% of voters say they would vote Conservative.
And polling for the prime minister shows a considerable loss of public confidence. According to YouGov just 24% of Brits believe Johnson is doing well, the lowest since he took office in 2019.
Elsewhere, 65% of the public believe that he is not competent at his job - also the highest figure since he became prime minister.
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