Reform UK is on course for a major upset in the Runcorn and Helsby by-election, according to the latest poll, despite a week of bitter infighting in the party.
The first poll of the constituency since MP Mike Amesbury quit after being convicted of attacking a constituent, forecasts Nigel Farage’s party will take the North West seat from Labour.
It comes after more than a week of rows in the insurgent right-wing party, with Mr Farage suspending one of its five MPs, Rupert Lowe.
In July’s general election, Mr Amesbury won the seat for Labour with 22,358 votes, with Reform UK a distant second on 7,662.
But, with Sir Keir Starmer’s popularity plunging since Labour came to power, the Lord Ashcroft poll found Reform is likely to pick up 40 per cent of the vote, with Labour on 35 per cent.
It is a blow for Sir Keir and will be a relief for Mr Farage, with recent surveys indicating Reform’s surge in popularity since the general election may have stalled.
As well as facing headwinds due to sluggish growth and Sir Keir’s decision to scrap winter fuel payments for millions of pensioners, Labour faced an uphill battle to retain the seat after Mr Amesbury quit in disgrace.
He was last month given a 10-week suspended prison sentence after pleading guilty to drunkenly punching a constituent, 45-year-old Paul Fellows, multiple times in the street.

The incident occurred on Main Street in Frodsham, Cheshire, in the early hours of 26 October, after Amesbury had been drinking. Upon arriving at a taxi rank, he was approached by Mr Fellows, who began to complain about a bridge closure in the town.
Footage showed Amesbury punch Mr Fellows in the head, knocking him to the ground, then follow him onto the road and start to punch him again, at least five times.
He was heard saying: “You won't threaten your MP again will you, you f****** soft lad?”
The by-election, the first since the general election, comes after Mr Farage suspended MP Rupert Lowe and said there was “no way back” into the party after a bitter row.

The pair have been at loggerheads since Mr Lowe questioned the Reform leader’s “messianic” tendencies, with the party revealing it had launched an investigation into his conduct just 24 hours after.
The suspension relates to “verbal threats” Mr Lowe is alleged to have made against Reform chairman Zia Yusuf. But Mr Lowe claims he is the victim of a political hit job.
The poll followed Labour selecting Cheshire West & Chester councillor Karen Shore as its candidate for the contest.
“Karen Shore will be a champion for the people of Runcorn and Helsby,” Sir Keir said.
“She’s local and her experience as a teacher and serving the community as a councillor will give people a strong voice in the House of Commons.”
Lammy warns it would be ‘wrong’ for Putin to put conditions on Ukraine ceasefire
Police given more time to question collision captain amid inquiry ‘complexities’
Tech secretary asks ChatGPT for policy advice
What could Labour abolish next after NHS England was scrapped?
Liz Truss spends taxpayer cash on CV training for former staffer
UK food and drink exports to EU down 34% since Brexit ‘due to red tape’