Much as the British people and their elected representatives may have wanted a break from politics during the platinum jubilee celebrations, the issue of the country’s political leadership has cropped up at many a street and garden party. “I would say that at all the events I have been to – and it is a lot – the vast majority have tried politely to avoid it where they can,” said one Tory MP with a southern constituency. “But about half a dozen people have searched me out to talk about Boris and every one told me he has to go. These were Tory people. They said they trusted me to do my duty in the coming days.” The same MP, who has not said publicly that Johnson should be ousted, although he has been critical of him, reported having received about 400 emails on the leadership question over the last few days, only four of which were at all supportive of the prime minister. “It is pretty overwhelming from people who normally vote Tory,” he said, giving an indication of his direction of thinking. The sense that support has been ebbing steadily away from Johnson has been borne out by accounts of jubilee parties related by other Conservative MPs. “People have not been big on politics because it is all about the Queen, isn’t it?,” remarked a former cabinet minister who is known to want to get the PM out of Downing Street as soon as possible. “But those who did mention it on the circuit said ‘well done for saying what you said’ … and they were all of the view that he must go.” It had also been widely noted among constituents, he added, that Johnson had been booed by a crowd full of royal enthusiasts outside St Paul’s Cathedral on Friday as he arrived with his wife Carrie: “His whole pitch has been that he is popular and that he is a winner. The reaction showed that he is not very popular any more. That kind of thing is going to happen again.” Another Tory MP from a northern seat reported that the reaction from his constituents had been more mixed and less predictable, with almost as many defending Johnson as wanting him out, though he too had picked up enough discontent to make him write to Sir Graham Brady, chair of the 1922 Committee of backbenchers, to demand a confidence vote. He had concluded that his effort to survive as an MP in a seat with smallish majority would be much better served by opposing the prime minister on doorsteps, than continuing to try to “defend the completely indefensible”. It is not completely impossible that this weekend – as the country marks the Queen’s seven decades on the throne – could be Boris Johnson’s last as prime minister. If that were to be the case, he will have served fewer than three years in Downing Street, even less time than his predecessor: Theresa May, whose short tenure he did so much to bring to a painful end as their disagreements over Brexit raged, lasted three years and 11 days. MPs return to Westminster on Monday. The leadership issue will be on everyone’s mind. The tension will be close to unbearable for Johnson and his supporters on the one hand, and those who want him gone on the other. The focus will be as much on Brady as on Johnson himself. For the past few days Brady, from his constituency of Altrincham and Sale West, has been monitoring the number of letters and emails that have been coming in from Conservative MPs demanding a vote of confidence in the prime minister. Even before the jubilee break about 30 Tories had gone public and called for the PM to go and well over a dozen more had been highly critical. Some of Johnson’s detractors said they sensed the magic number had been all but reached even before they left for their constituencies 10 days ago. Once it does hit 54, Brady has to contact the prime minister at the earliest opportunity to let him know the bad news and to arrange a secret ballot of the 359 Tory MPs. One senior Tory source said: “If we hit the number, then it happens as soon as it realistically can. Obviously if the Russians invade East Anglia there would be some leeway, but unless there are unforeseen events the vote would be within a day or two.” It might be that the number reached 54 some time over the last few days and that Brady – mindful of the need not to let a political crisis overshadow the jubilee – delayed saying so until the parties and concerts were all over. Brady won’t say. Only he knows the figures. None of his staff have access to the letters and emails. The rules state that if there is a confidence vote then Johnson needs to win a majority (180) to stay as Conservative leader and remain prime minister. If he does win the rules state that there cannot be another confidence vote for at least a year. But Johnson and every Conservative MP knows it is not just about winning: other factors also determine whether a leader survives to fight another election. It is also about the margin of victory and the number of rebels. When Theresa May was subjected to a confidence vote in December 2018, she won with 200 MPs expressing their confidence in her and 117 saying the opposite. So almost twice as many of her MPs and ministers backed her as did not. But without a Conservative majority in the Commons after the 2017 general election, she was terribly weakened at a time when she desperately needed numerical strength to get her Brexit deal through parliament, and within six months she had resigned. Johnson’s starting position looks far stronger. He has a working majority of 75 in the Commons, taking into account the non-voting Speaker and his deputies, as well non-sitting Sinn Féin MPs. But while he is very likely to get a simple majority, the big question exercising many of his critics and his defenders this weekend, is how many might turn against him once the contest has been called. “This is the key,” said one Tory rebel. “If somewhere between 75 and 100 were to vote against him I think he would be in big trouble. He would carry on but it would be far more difficult for him to govern at a time of economic difficulty, and far more difficult to get legislation through.” This is why some rebel Conservatives – including a number who have already put in letters to Brady – now believe it would be best to delay a confidence vote until after two critical byelections on 23 June, in Tiverton and Honiton, where the Tories are under threat in a normally safe Conservative seat from the Liberal Democrats, and in Wakefield, where Labour is expected to seize back one of the traditional strongholds it lost to the Conservatives in 2019. If the Conservatives were to lose both contests in a wave of anger against Johnson over Partygate, then there is a feeling within the party at large that all bets could be off. “It will be at that moment that the message would really get through to colleagues that rather being an election winner, our leader has become an election loser,” said the Tory rebel. “So for those of us who want him out it might well be best to wait until the moment of maximum danger, and that is probably around 24 June.”