Labour could be swept into power with a landslide of more than 400 seats at the next general election, according to the latest YouGov mega poll.

The survey of 18,000 people predicts Sir Keir Starmer’s party will win a parliamentary majority of 154 – almost double what the Conservatives achieved with Boris Johnson in 2019.

The poll forecasts Labour will win 403 seats, a gain of 201, while the Tories will crash to just 155 seats – a loss of 210.

Follow live: The big Tory names forecast to lose their seats

If correct, the result would be a worse defeat for the Conservatives than under Sir John Major in 1997, when the rise of Sir Tony Blair‘s New Labour left them with just 165 MPs.

Key Conservatives projected to lose their seats include Chancellor Jeremy Hunt, cabinet ministers Grant Shapps and Penny Mordaunt and former party leader Sir Iain Duncan Smith.

A loss for Ms Mordaunt would be particularly embarrassing as she has been already a two-time contender for the party leadership, and has been touted as a potential successor to Rishi Sunak.

Other cabinet ministers set to lose their seats include Transport Secretary Mark Harper, Justice Secretary Alex Chalk, Science Secretary Michelle Donelan and Wales Secretary David TC Davies.

There is also bad news for the SNP, which is forecast to lose 29 seats, with most of them going to Labour.

That would mean Labour once again becoming the largest party in Scotland, having been virtually wiped out north of the border in 2015.

Meanwhile the Liberal Democrats, who are targeting Conservative heartlands in southern England, are forecast to gain 38 seats, giving them 49 in total.

This includes in Mr Hunt’s new Godalming and Ash constituency (formerly South West Surrey), where he has a majority of 8,817 votes.

The poll was conducted by YouGov between 7 and 27 March, and it used a multi-level regression and post-stratification (MRP) process to model constituency-level results.

Read More:
Labour can take comfort as ‘mega’ poll shows they are on right path – but remain wary of complacency
Tories in ‘dire position’ and ‘good MPs will lose seats’ at general election

It is generally considered one of the most accurate forms of polling due to the number of interviews conducted, which enables pollsters to examine voting intentions in very small geographical areas.

It is the latest in a series of disastrous polls for the Conservative Party ahead of a general election expected in the second half of this year.

Tory MP Brendan Clarke-Smith, who is projected to lose his seat to Labour, posted on X that the polling model is “clearly flawed and fails to factor in my infectious charm and charisma”.

Politicians are often sceptical about opinion polls, and many of YouGov’s predictions will no doubt by queried by MPs and party officials in the coming days.

Despite a double-digit lead in the polls for some time now, Sir Keir Starmer has imposed an iron discipline on his shadow cabinet about the danger of complacency.

While some pundits predict the next election will be a repeat of the party’s 1997 landslide victory, there are fears within Labour of a 1992 false dawn – when Neil Kinnock lost what was believed to be an “unlosable” election.

The 154-seat Labour majority in the new poll is edging towards the 179-seat majority won by Tony Blair in 1997, though well short of a 254-seat majority suggested in another MRP-style poll in mid-February.

If Labour were to win the next election, it would bring an end to 14 years of Conservative government under five prime ministers.