The PM will be hoping the dissatisfaction among his MPs – which saw nearly 100 backbenchers defy the party whip to vote against the Government on Tuesday – is not felt more widely, as the Conservatives battle to keep the seat of North Shropshire in a key by-election on Thursday.
It comes after nearly a third of his MPs voted against the introduction of mandatory Covid passes in nightclubs and large venues, with many saying they were unhappy about the way Mr Johnson was leading the country and his party.
Sir Geoffrey Clifton-Brown treasurer of the 1922 Committee, said that a leadership challenge has “got to be on the cards” for Mr Johnson in the new year if he did not change the way he worked with his MPs.
While former Tory chief whip and leading rebel Mark Harper said: “You either listen and you respond and you do things differently or you ignore what you have been told and you plough on regardless and then this will happen over and over again.”
Some 126 MPs voted against regulations to make Covid passes – also known as vaccine passports – mandatory in some venues, with fines for establishments that refused or those who faked the documentation.
This included 97 Conservatives, according to the division list, but Tory MP Steve Baker said he believed there were two more votes against – which had not been reported in the list – bringing the total to 99 Conservative rebels, plus two tellers for the noes.
In recent months, division lists have been updated to include names not initially published.
The measures still passed, as Labour had supported the Government in the vote.
But Labour leader Sir Keir Starmer said: “The Prime Minister needs to take a long, hard look at himself and ask himself whether he has the authority to take this country through the pandemic. This is a very significant blow for him.”
Other measures under the Government’s Plan B also cleared the Commons, including to drop the requirement to isolate and instead do daily Covid tests for those fully vaccinated people who are contacts of a positive Covid case.
MPs also approved mandatory vaccinations for NHS and social care staff by April 2022 and the requirement to wear face coverings to more indoor spaces in England – including museums and galleries.
Some 61 Conservatives also voted against the mandatory vaccination plans.
The size of the rebellion against the Covid passes came as a surprise after the PM had personally intervened to try and talk around rebels earlier in the evening by delivering a speech at the 1922 Committee of backbench MPs.
Sir Charles Walker, the vice-chairman of the committee, said the rebellion was a “cry of pain” by the party.
He told BBC News: “This was just a bridge too far. I think they were putting a marker down. It was a cry of pain from the Conservative Party.
“He (Boris Johnson) is in a very, very, very difficult position. There has been a strong view in within the Conservative Party that vaccine passports do not work and is not something many colleagues wanted to see introduced.
“This is a very, very specific line being drawn in the sand now and I think the Prime Minister and his team need to listen.”
The message from MPs comes as many are still angry over the revelations of alleged parties and gatherings held in Downing Street and elsewhere during lockdown restrictions, as well as longer held resentment about the Government’s handling of the standards row involving former MP Owen Paterson which led to Thursday’s by-election.
On Tuesday night, a photograph emerged in the Daily Mirror of a previously reported party held by Tory mayoral candidate Shaun Bailey’s campaign team on December 14 last year.
Mr Bailey quit the London Assembly’s Police and Crime Committee ahead of the publication of the photograph.
While the Mirror also reported No 10 staff who stayed in Downing Street to take part in a Christmas quiz on December 15 were told to “go out the back” after the event.
Cabinet Secretary Simon Case has been asked to investigate, and could report back as early as this week.
A Government spokesperson said: “Given there is an ongoing review, it would be inappropriate to comment while that is ongoing.”
But the Liberal Democrats, who say they are now “neck and neck” with the Tories in the North Shropshire poll, said the various scandals would hit the party – which previously enjoyed a nearly 23,000 majority in the seat – at the ballot box.
Liberal Democrat health spokesperson Daisy Cooper said: “From No 10 to Tory HQ, the slew of rule-breaking revelations show that Boris Johnson has set a very low bar for standards within his party and his presence in Downing Street is eroding public trust.
“This Thursday, voters in North Shropshire have the chance to tell him the party is over.”