Every month, the ConservativeHome website carries out a survey of its party member readers to find out their views including the regular cabinet satisfaction ratings.

The latest survey sees the current occupant of Number 10, Boris Johnson, rated with a net satisfaction level of minus -15%. By a long distance, these are the worst numbers for anybody on the list.

Ben Wallace leads the pack on +85, Nadhim Zhahawi is second on +66.2 – and a name not well known out of Tory circles, Anne-Marie Trevelyan comes in third at +64.6. Alarmingly, Liz Truss lies in fourth place at +64.3.

However, for Boris Johnson, lying at the very bottom of the list of 32 MPs at -15, with Brexit’s biggest mouthpiece Ben Elliot just above at -0.4, things do not look good.

The latest fortnightly Opinium poll is out and the message from those sampled is clear – they want the PM out and they want him to go straight away.

The FT reports that – senior Conservative MPs said on Monday (30/05) that Boris Johnson was likely to face a vote of no confidence in his leadership of the party if the Tories lose two parliamentary by-elections next month. Two more Conservative MPs on Monday called for the prime minister to quit following the partygate scandal, including former attorney-general Jeremy Wright. Wright said the affair had done “real and lasting damage” to the government’s reputation, adding: “For the good of this and future governments, the prime minister should resign.”

It is reported that a total of 26 Tory MPs have now publicly called on Johnson to quit, albeit that the number is actually likely to be exceeding 40. The damning report last week by senior civil servant Sue Gray into the partygate scandal has become the last straw for some. For a vote of no confidence in Johnson’s leadership to take place, 54 Tory MPs must submit letters requesting a ballot to Sir Graham Brady, chair of the 1922 Committee of Conservative backbenchers.

However, the last straw really is almost upon Boris Johnson. Possibly.

The more silent MPs sending in letters requesting a no-confidence vote have trickled from those who could face a strong challenge from Liberal Democrat parliamentary candidates at the next general election.

But now, some senior Conservative MPs have said that if the party lost two by-elections in Tiverton and Honiton in Devon and Wakefield in West Yorkshire on June 23, it could prompt more Tories to submit letters to Brady and ensure that the 54 threshold is reached.

The Lib Dems are aiming to seize Tiverton and Honiton from the Conservatives, while Labour is seeking to secure Wakefield from the Tories. At the last general election, the Tories had a huge majority of over 24,000 on an electorate of just 82,000 at Tiverton and Honiton. For Wakefield, the story is different. Its electorate in 2019 was 70,000 and the Tory majority was just over 3,000.

It is likely that Tiverton and Honiton will be held. The last four general elections have resulted in strong wins, the strongest win yet was in 2019. Wakefield is likely to fall, leaving a draw. However, if the majority in Tiverton and Honiton is greatly reduced – the likelihood of more letters arriving at the 1922 committee to reach the magic 54 is very likely.

Currently, the betting odds for Johnson leaving No10 this year are 7/4. Not good for the PM.

For Johnson, the decision is clear: against all the odds, he won London twice, the EU referendum and the 2019 election. He’s never lost a national election that he stood in. As one Tory MP said – “Do you really want to swap him out for someone who has zero track record of winning an election?”