Labour has stormed to a 25-point lead in the polls —enough to secure a landslide bigger than that secured by Tony Blair in 1997.
Support for the Tories has more than halved since the earliest days of Covid, data shows.
Meanwhile Reform UK has capitalized on the Conservative decline, with the Nigel Farage-backed outfit standing just 10 points behind.
YouGov's new polling results come as Rishi Sunak today hit the election campaign trail urging Brits to back his 'bold vision' after shocking the country — and his own MPs — by announcing a July 4 contest during a speech in the pouring rain outside Downing Street yesterday.
The PM joked he is 'drier' than yesterday and had 'brought an umbrella' as he sought to wrangle public support for his summer election gamble.
He launched a personal attack on Keir Starmer, swiping that he had 'no convictions' and voters cannot trust him.Mr Sunak also suggested that the Labour leader would make the UK a 'magnet' for Channel boats.
The scale of the task facing the Prime Minister was underlined by YouGov's research showing Labour 25 points ahead.
Support for Labour stood at 46 per cent, with the party having suffered a minor blip over the past fortnight.
This compared to the Tories on 21 per cent, marking a slight uptick since support fell to its lowest levels since the Liz Truss meltdown.
The PM joked he is 'drier' than yesterday and had 'brought an umbrella' as he sought to wrangle public support for his summer election gamble during interviews in Derbyshire this morning
Yesterday's shock election announcement came hours after official statistics showed inflation had fallen to 2.3 per cent. Mr Sunak will put the improving economic picture at the heart of the election campaign.
Conservative sources claimed Mr Sunak had been weighing up the pros and cons of a summer election for weeks.
Tory strategists believe that Labour's lead is 'soft', and point out that up to a third of voters are still saying they have not made up their minds how to vote.
Mr Sunak also received a huge boost as Nigel Farage dramatically killed off hopes of a comeback after months of uncertainty. The Brexit champion insisted he wants to focus on backing Donald Trump's campaign in the US, as he announced he will not be a candidate for the Commons.
Polling guru Sir John Curtice said Mr Sunak's decision to call a ballot meant that he is 'either very brave or extremely foolhardy'.
The decision sparked jitters on the Tory benches, with some fearing it could lead to electoral wipeout.
One senior Tory branded the move 'suicidal'. Cabinet Office minister Esther McVey urged Mr Sunak to wait until the autumn to allow more time for the benefits of rising real wages to filter through.
Mr Sunak told GB News: 'If you elect me, if I'm Prime Minister on July 5, those flights will go off to Rwanda and we will begin to put in place the deterrent that we need to stop the boats.
'There is no way to stop this problem unless you can have a deterrent, unless it's clear that if someone comes to our country illegally they won't be able to stay and they will be removed.
'Unless you're able to deliver that people will keep coming.'
The campaign got off to a less than auspicious start last night as Mr Sunak announced the summer election in a dramatic - and soaking wet - Downing Street statement.
As his suit became drenched, and with protesters playing the New Labour anthem of 'Things Can Only Get Better' in the background, Mr Sunak pointed to inflation being 'back to normal' and insisted he was 'stopping the boats'.
'The question now is how and who do you trust to turn that foundation into a secure future... now is the moment for Britain to decide its future,' he said.
Even his own Cabinet was kept in the dark until the last minute, with Mr Cleverly telling ITV's Peston 'we don't get particular advance notice' and it was largely a matter for Mr Sunak and his inner circle.
The news caused disquiet among Tory MPs fearful of losing their jobs, and those who have already said they will not stand and are having to say goodbye to Parliament sooner than expected.
Despite speculation at Westminster about a Tory rebel effort to oust Mr Sunak and call off the election, one prominent critic of the Prime Minister said it was 'too late' to get rid of him.
Dame Andrea Jenkyns, who has called for Mr Sunak to go, said she understood 'other letters have been going in' to 1922 Committee chairman Sir Graham Brady but 'colleagues, it's too late, I told you six months ago we should have done this'.
Mr Sunak also received a huge boost as Nigel Farage dramatically killed off hopes of a comeback after months of uncertainty. The Brexit champion insisted he wants to focus on backing Donald Trump's campaign in the US, as he announced he will not be a candidate for the Commons
The campaign got off to a less than auspicious start last night as Mr Sunak announced the summer election in a dramatic - and soaking wet - Downing Street statement
Party whips from the Conservatives and Labour are holding talks to work out what outstanding legislation can become law before prorogation – the end of the current parliamentary session – on Friday.
That includes the Victims and Prisoners Bill, which includes measures to establish a compensation scheme for victims of the infected blood scandal.
Sir Keir responded with his own statement last night saying he welcomed 'a moment the country needs and has been waiting'.
'A chance to change for the better your future, your community, your country,' he said.
'It will feel like a long campaign, I am sure of that, but no matter what else is said and done, that opportunity for change is what this election is about.'
Mr Sunak launched a highly personal attack on Keir Starmer, swiping that he had 'no convictions' and voters cannot trust him
