Boris Johnson set to lose his seat in an election pasting, with the Tories losing 85 battleground races, a new poll has predicted.
It comes amid rising concern among Conservative MPs that Mr Johnson’s premiership is not salvageable - and he may take them all down with him.
All but three ‘red wall’ seats that turned Tory in the 2019 election would return to Labour if the election was held tomorrow, the YouGov poll found.
And the Prime Minister would be beaten by Labour in his own seat of Uxbridge and South Ruislip, with Keir Starmer ’s party holding a five point lead in the seat.
Meanwhile, every ‘blue wall’ battleground seat in the South and London would fall to Labour, including Iain Duncan-Smith’s constituency of Chingford and Woodford Green and Steve Baker’s seat in Wycombe.
The Tories are also predicted to lose every seat they hold in Wales.
Former minister David Davis said his colleagues "see their own seats disappearing" as Tory popularity continues to languish in the wake of the so-called partygate saga.
And ex-health minister Steve Brine was discovered to have added his name to the list of Tory MPs to have handed in letters of no confidence in the Prime Minister.
Sir Graham Brady, chairman of the 1922 Committee of backbench Tories, will be obliged to order a confidence vote if he receives 54 letters demanding one.
Currently, 23 MPs have publicly stated that they no longer support Mr Johnson.
Mr Brine said Ms Gray's report had not altered his view that it was "inevitable the Prime Minister would face a vote of confidence".
"All I can do as a backbencher is seek to trigger that process and (some time ago actually) I have done that," he confirmed in a statement published on his website on Wednesday but only picked up by the media on Saturday.
"I have said throughout this sorry saga I cannot and will not defend the indefensible. Rule-makers cannot be law-breakers."
The band of rebels increased on Friday, with Sir Bob Neill, Conservative chairman of the Justice Select Committee, confirming he had submitted a letter of no confidence in Mr Johnson's leadership.
Alicia Kearns, a member of the 2019 intake, accused the No 10 incumbent of "misleading" Parliament with reassurances that coronavirus laws were upheld.
Cabinet Office official Ms Gray detailed in her report how leaving-dos got out of hand, with staff throwing up after drinking excessively, being rude to security staff and even damaging a child's swing in the Downing Street garden.
She found the Prime Minister - who was slapped with a fine by police for attending his own birthday bash in June 2020 when indoor mixing was forbidden - attended a number of leaving-dos in No 10 during the lockdown months in England.
Ms Gray said he gave speeches and joined in with drinking alcohol at such events despite the public being banned from socialising in a bid to stop the spread of the virus.
The warning by Mr Davis of increasing mutiny comes after polling company YouGov produced new modelling suggesting the Conservatives would lose all but three of 88 "battleground" constituencies if a general election were held on Saturday, putting the Government's Commons majority in jeopardy.
The predicted outcome would see Mr Johnson's own Uxbridge and South Ruislip seat "likely fall" into Labour hands and Red Wall seats such as Blyth Valley and Stoke-on-Trent North also revert back to Sir Keir Starmer's opposition.
Only Ashfield, Bassetlaw, and Dudley North would remain blue, according to YouGov.
James Johnson, a former Downing Street pollster during Theresa May's tenure, said the results could prove to be even worse than the model predicts.
"Remember that MRP does not pick up tactical voting or local seat effects," he said on Twitter.
"Tactical voting helps Labour and the Lib Dems at the moment, so it's highly likely that the current picture for the Conservatives is even worse than this polling indicates."
Mr Davis, a former Brexit secretary, told BBC Radio 4's Today programme that potential Tory losses and the "distraction" of questions about the No 10 parties was focusing minds in terms of thinking about the party's leadership.
He implored Mr Johnson to quit in January, telling him to "in the name of God, go", and said he had not "changed my mind about that".
Asked whether discontent was spreading in the Tory party, Mr Davis said: "There is no doubt about that, for two reasons.
"Number one, frankly they see their own seats disappearing in many cases, they see themselves losing the next election on the back of this.
"Also, it has a bad effect on the country ... it is a distraction on everything you do and it doesn't help the reputation of the country."
Despite facing criticism over his partygate defence, the Prime Minister chose to announce changes to the ministerial code this week in a move his rivals said watered down punishments for ministers.
An update said ministers will not automatically lose their jobs if they breach the standards code, and can instead apologise or possibly have their salary suspended instead.
Chris Bryant, the chairman of the Commons Standards Committee, told the Today programme the move demonstrated why an independent process was required when it came to judging possible ministerial wrongdoing.
The Labour MP, who has recused himself from chairing the Privileges Committee investigation into whether Mr Johnson misled Parliament with his partygate reassurances, said the current system means "it still all lies in the Prime Minister's hands and we know that the Prime Minister always finds himself innocent in the court of his own opinion".
