The long-standing Labour MP Dennis Skinner is at risk of losing his seat in Bolsover.
According to Best for Britain polling Skinner could lose his Derbyshire seat to the Conservatives, despite taking a pro-Brexit stance.
The MP has held the seat since 1970, but now appears to be at risk from the local Tories.
The polling puts Skinner on just 28% of support – down by 23% at the last election – compared to the Tories at 34%.
Despite his Brexiteer credentials, Best for Britain are advising people vote tactically in the seat to support Labour to deny Boris Johnson a majority.
If Skinner is re-elected he will replace Ken Clarke as father of the house.