Labour is on course for a 140-seat majority at a snap election, a major new poll has suggested.
Keir Starmer’s party would scoop 470 seats to just 129 for the Tories and 26 for the SNP if a national ballot was held tomorrow, according to the survey for Best for Britain.
But the large-scale research, using the controversial “multilevel regression and poststratification” method, found Labour’s lead was vulnerable to Rishi Sunak wooing large numbers of undecided voters - and the threat from Nigel Farage’s Brexit vehicle Reform UK.
If wavering Brits go over to the Tories and Reform stands aside for the Conservatives in marginal seats then the model predicts a hung Parliament. Labour would win 316 seats, with the Tories on 286 in this scenario.
The mega-poll is the first of its kind to take account of new constituency boundaries which will be in play at the next election.
Labour's vote share would be 35%, giving them a 12 point lead on the Tories who would take 23% of the vote. There are 12% of voters who are undecided.
But Labour's lead has slipped by 7 points since a similar poll in the Autumn.
Best for Britain chief executive Naomi Smith told a Westminster press briefing: "That Labour lead is significant, but it is smaller than last time we did it.
"Our read of our data is that Sunak has managed to win back some of those Tory voters disaffected by the Truss-Kwarteng disaster budget."
But she said Labour was on track to pick up seats in Scotland in all scenarios following the SNP chaos - a key step to winning a majority.
The research found that 206 of 632 seats in Britain are marginal, with Labour either in first or second place in 197 of these narrowly held constituencies.
Scotland, the East of England and the South East are likely to be important battlegrounds - holding half (101) of the marginal seats Labour would hope to win.
Polling guru Professor Sir John Curtice said the Tories were "a long way behind" in the polls - and they would struggle to form a minority Government "as they don't have any friends in the House of Commons".
He said Partygate and Liz Truss's disastrous mini Budget have had "very substantial impacts on the overall levels of party support" for the Tories.
Luke Tryl, UK director of the More in Common thinktank, said focus groups were showing support for Labour but the lead was still "quite soft".
"You've got the potential for quite a large and quite significant Labour victory in the next election. But it is quite soft," he said.
"A lot of it at the moment seems like Labour winning by default, rather than having won over lots of people."
He said focus groups repeatedly showed people were exhausted by political chaos and believe that nothing in Britain works properly.
Mr Tryl said: "Against that backdrop is quite easy to see why the Conservatives are struggling.
"You add into that this perception that not only are things not going that well and a little bit chaotic, but that the Conservative Party is to some degree that cause of that chaos, and you really get this perfect storm for them."
Voters often question whether Rishi Sunak is "strong enough", which is "particularly exacerbated by the constant returns to the stage of Boris Johnson," he said.
"In one focus group in Surrey, one woman said, 'Yeah, but that's the problem with little Rishi, he just can't stand up for us on the world stage."
The Prime Minister is seen as competent but this advantage risks being eroded by the sense he isn't in control of events, Mr Tryl warned.
:: Poll of 10,102 GB adults by Focaldata commissioned by Best for Britain conducted between 20 April and 9 May
* Follow Mirror Politics on Snapchat, Tiktok, Twitter and Facebook.
