ishi Sunak is braced for a possible triple by-election blow after polls closed in contests which will be viewed as a test of his leadership.
The Prime Minister has acknowledged that holding the seats, including Boris Johnson’s former constituency, will be a “tough battle” and Tory allies have said the contest the party is focused on is the general election next year.
For Labour, winning the Uxbridge and South Ruislip seat vacated by Mr Johnson, and the Selby and Ainsty constituency formerly held by his ally Nigel Adams, would be a major boost for Sir Keir Starmer.
In Somerton and Frome, in a contest triggered by the resignation of scandal-hit David Warburton, the Liberal Democrats hope to add to a series of eye-catching recent by-election victories.
Losses for the Tories in all of them would be the first time in 55 years that a government has been defeated in three by-elections on the same day.
While Mr Johnson only held his seat with a majority of 7,210 as he led the party to a national landslide in 2019, the Tories had a cushion of about 20,000 votes in the other two constituencies, so losses would increase Tory pressure on Mr Sunak.
The Prime Minister could attempt to reset his administration with a Cabinet reshuffle in the wake of the contests – Defence Secretary Ben Wallace has already signalled he will exit the Government so there is a vacancy to be filled – although No 10 has publicly said there are no plans for a shake-up.
Mr Sunak would need to decide whether the benefits of freshening up his team at this stage would be outweighed by the risk of it being perceived as a panicked response to an electoral setback.
A Conservative spokesman said: “There’s no doubt that this was always going to be a very challenging set of by-elections, especially given the circumstances in which they were brought about.
“We have to wait for the results to come in, but by-elections are rarely won by governing parties and they are rarely good indicators of general election performance.
“Across all of these campaigns we have heard zero enthusiasm for Sir Keir Starmer’s Labour Party and their lack of answers.
“We now need to redouble our efforts earning back the trust of voters by delivering on our plan to halve inflation, grow the economy, reduce debt, cut waiting lists and stop the boats.”
On Wednesday Mr Sunak told a private meeting of his MPs that he would show people “who is really on their side” at the next general election, adding: “And that is what will propel us to victory.”
He was conscious of the battle he will face if voters roundly reject the Tory by-election candidates, but urged MPs to unite ahead of a general election expected next year.
“When we come back in September we have a choice to make, all of us. Do we come together and throw everything at winning the next election or not? I’ve made my choice, I’m all in with you to win,” Mr Sunak told the meeting.
“I promise you we can do this but we can only do it together as one team.”
In Uxbridge and South Ruislip, Labour’s Danny Beales hopes to defeat Tory Steve Tuckwell, although rows over the Mayor of London Sadiq Khan’s decision to extend the Ulez low emission zone may cost Labour votes.
In Selby and Ainsty, Keir Mather, 25, will become the new Baby of the House if he wins for Labour, with Tory Claire Holmes trying to retain the seat for her party.
Somerton and Frome has Sarah Dyke hoping to win for the Liberal Democrats, while Faye Purbrick wants to ensure it stays Conservative.
A Labour Party spokesman said: “It’s going to be some time before we get any results. But what we do know is that none of these seats have ever had a Labour MP before, so they were always going to be a challenge.
“We didn’t even win Uxbridge in 1997 and to win Selby and Ainsty would require us to overturn the biggest majority in our history.
“So while we don’t know if we’ve made it over the line, it’s clear that Keir Starmer’s leadership of a changed Labour Party, back in the service of working people, has seen voters put their trust in us – many for the first time.”
Lib Dem leader Sir Ed Davey used an email to party supporters to claim “we’re on for another historic result” and “I’m confident we will win big tonight” in Somerton and Frome.