Boris Johnson has insisted he will remain in No10 despite a series of high-level resignations over the Chris Pincher scandal.
But his determination to remain in office may not be enough to secure his future, as those in his party who want him gone appear to have mapped out their next move.
Politics Hub: More resignations earlier in the day as pressure mounts on PM – live updates
It all boils down to the top level of the 1922 Committee – the organization that represents Tory backbenchers in the House of Commons.
Its ruling executive consists of 18 members, including six officers – a chairman, two vice-chairmen, two executive secretaries and a treasurer.
And they have a lot of power in the party – especially when it comes to removing leaders.
The leader of the 22ers, as he is known – currently Sir Graham Brady – is usually the one who makes the headlines as he is the only person who knows how many letters of no confidence against the Prime Minister have been tabled by backbenchers.
They are then tasked with announcing when the number crosses the threshold to trigger a vote of confidence, as Mr Johnson knows only too well.
The prime minister won one such vote in early Juneand under the current rules of the committee, he cannot be challenged again for another 12 months.
But here’s the catch: the Executive Committee can change the rules if it wants to. And it will meet tonight (Wednesday) at 5pm to discuss the prospects.
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Is this likely?
It’s happened before.
After a string of losses in Parliament over her Brexit deal, the committee agreed to change her to challenge Theresa May’s leadership for six months after winning a vote of confidence.
However, it never got to that stage. Sir Graham reportedly informed her that a decision had been made about a rule change, but before going into detail, she gave the date of her departure.
For the past few weeks, existing members of the Executive Branch have been lukewarm to the idea of changing the rules – fearing the precedent it would set for future leaders.
But that should not reassure Mr. Johnson, as this executive’s appointment is about to change.
Every time there is a Queen’s speech and a new session of Parliament begins, the top 22’s run for re-election – meaning a vote is due.
Sir Graham is expected to announce the opening of nominations later today, with the first meeting to swear in the new executive next Wednesday and the first opportunity to change the rules the following week.
That means if the rules were changed to allow the Prime Minister a second vote of confidence, it could potentially happen the day before MPs leave Westminster for their summer recess on July 21.
Tory MP Andrew Bridgen, who is an outspoken critic of the Prime Minister, has already announced he will be a candidate backing a manifesto to change the rules to allow Mr Johnson another vote of confidence.
It is likely that other potential board members will follow the same path.
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Can the PM do anything about it?
There have been rumors that No. 10 may be trying to find some loyalists to introduce themselves as well, to ensure critics of the current leadership don’t uphold the balance of power.
But the executive branch is elected only by backbench MPs, not by those on the government payroll.
Up to three-quarters of the backbenchers may have voted with distrust last time out, making the strategy unlikely to pay off.
The election of an executive committee of an obscure backbench organization might seem like uninteresting internal administration, but it could have major implications for the Conservative Party’s leadership and, by extension, the country’s leadership.