Labour is on course for the biggest election victory in a century, winning with a majority of 194, according to a new YouGov megapoll. 

Meanwhile, the SNP could be reduced to just 17 MPs, their worst result since 2010. 

The results of the MRP survey carried out for Sky News were published just hours before the first televised debate of the campaign.

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If the poll of 53,334 people in England and Wales and 5,541 in Scotland is correct, it could mean the Tories are set for their worst result in recent history, winning just 140 MPs.

Labour would win 422 MPs, giving them a 194-seat majority, the highest number since Stanley Baldwin won with a majority of 208 in 1924.

The Lib Dems would get 48 seats according to this projection, up 40 on 2019.

In Scotland, the poll predicts Labour will win 34 seats, the SNP down 31 on 17, the Tories five and the Lib Dems one.

YouGov suggests that the SNP "could be entirely ejected" from Glasgow, with Labour predicted to take all six of the city's constituencies.

Although the pollster says Glasgow North and Glasgow North East are "tossups."

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What will be terrifying for the Tories is the fieldwork was carried out before Nigel Farage announced that he would be taking over as the leader of Reform and running for Parliament. 

The surprise bid for a Westminster seat comes after he insisted he was going to sit this vote out to help Donald Trump campaign for the White House. 

He said he changed his mind after people kept asking him why he wasn’t standing. He said he felt he was letting them down.

Given how marginal many of the Tory seats are, a revived Reform could do Rishi Sunak's party real damage.  

They were already doing poorly in the polls.

Even Douglas Ross, the Scottish Tory leader struggled to answer when asked if he thought Mr Sunak would win the General Election.

The Herald had to ask the Holyrood Tory leader three times if he thought his party would triumph on July 4.

He initially replied: “Well, I'm looking at the response we're getting on the doorstep here in Scotland.

“I've been in East Renfrewshire, I've been in Moray, up in in the North East, in Glasgow today, going down to the borders later on and right across the country people can see in key seats where it's a straight choice between the Scottish Conservatives and the SNP, they're uniting behind the Scottish Conservatives.”

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Asked again if he thought the Tories would win, Mr Ross said: “I'm answering your question very specifically, by saying the opinion polls are not reflective of what I'm hearing on the doorsteps.

“In any part of Scotland I'm going to at the moment people can see that in key seats it's a straight choice between the Scottish Conservatives and the SNP and they are uniting behind the Scottish Conservatives, because of the way the SNP have handled public services here in Scotland for the last 17 years, 16 of which John Swinney has been at the heart of.”

Asked for a third time if Mr Sunak and the Tories could win the election, Mr Ross replied “Absolutely, and what I'm saying is that here in Scotland, people are uniting behind the Scottish Conservatives to beat the SNP, and that is the message that I'm taking out in key seats across the country.

"And we're getting a very positive response to that.”