Two years ago, the Sun was on hand to capture the moment of Boris Johnson’s election triumph. A year later, the court photographers were present again when the Prime Minister celebrated the achievement of his Brexit trade deal with the European Union.

Unsurprisingly, none were at Johnson’s side when the potentially fateful result of the North Shropshire by-election came rolling in. The 23,000-strong majority bequeathed by the disgraced Owen Paterson was brushed aside as the Liberal Democrats surged from third to first, topping out with 6,000 more votes than the Tories. Labour’s campaign turned out to be an irrelevant sideshow.

Extrapolating consequences from by-elections is a fraught business. If similar swings were repeated at a general election, the Tory party would be eviscerated—but if history is any indicator, the chance of that is next to nil.

In 1991, the Lib Dems took Ribble Valley in a spectacular by-election victory. Their 25-point swing was a lot less spectacular than last night’s, but it appeared to put John Major’s Tories on notice for a drubbing in 1992. Instead, Major secured a fourth Conservative term and the constituency returned to his party, where it has remained ever since. Given the character of North Shropshire—relatively affluent, home-owning, rural, and Leave-voting—the tea leaves suggest Helen Morgan, the newly-minted MP, won’t be in her new job for long.

That isn’t to say what happened in North Shropshire is not without significance. The story of Boris Johnson’s premiership had, until recently, seemingly defied the laws of political gravity. He has hitherto shirked blame for 150,000 Covid deaths. The scandal of PPE procurement has not touched his government. The blunders and mistakes of the last eighteen months—Eat Out to Help Out, the free school dinners debacle, Universal Credit cuts, supermarket shortages, energy price rises, the Afghanistan humiliation, and the stripping back of the ‘levelling up’ fund—have depressed the excessive rating Johnson and the Tory party enjoyed at the beginning of the pandemic.

But the pollsters kept reporting a solid core of around forty percent of the electorate who were sticking by them. Since Partygate and Johnson’s lies about whether social gatherings took place last Christmas, this phalanx of hardened voters have been broken where the everyday hullabaloo of politics has failed. Who might have guessed flouting Covid precautions by which everyone had to abide would hit Johnson hard? The by-election shows this anger has made inroads into swing and loyal Tory voters alike, and will present the party with a problem come the next election.

When Prime Ministers are found out, their authority dribbles away and it’s next to impossible to stage a comeback. It appears Johnson is entering this territory, and the knives are getting sharpened.

So can Johnson survive? The press pack consensus, undoubtedly fanned by texts from friendly Tory MPs, suggests he has until next May’s local elections to restore the Tory position. But the end could come sooner. Having ninety-nine MPs rebel against Covid certificates is one thing, but on Tuesday thirty-eight rebelled against mask mandates—a cheap, simple, and yet very effective means of mitigating Covid transmission.

With a solid ball of reality-denying malcontents combined with backbenchers spooked by the result, they’ve seeded Johnson’s parliamentary party with gunpowder which could combust, especially if the government is forced to introduce more restrictions—moves that are very likely given the increasing rate of infection and inevitable rise in hospitalisations. It’s going to take a lot of arm-twisting to prevent the no confidence vote from being triggered at a moment of acute crisis.

Who are the beneficiaries of Johnson’s demise? Lobby hacks’ text messages have lit up with the names of Rishi Sunak and Liz Truss in recent weeks, though it would be foolish to discount Priti Patel, Michael Gove, and Dominic Raab from throwing their hats in the ring. But assuming Truss and Sunak are the frontrunners, both lack the broad appeal Johnson once commanded.

Sunak’s urbane, suit-and-briefcase countenance and (seeming) ease with liberal Toryism makes him the heir to David Cameron, albeit with Brexity characteristics. His first instinct is to revive traditional neoliberalism just as businesses and the class relations they depend on could do with a more hands-on state. A cuts programme is unlikely to find favour with nervous red wall Tories, nor with the self-styled social conservatives who made a nuisance of themselves during the Cameron years.

Truss comes at it with the opposite problem. Having cosied up to new Tories, the so-called Northern Research Group and the overlapping anti-mask faction, she has the advantage of being the face of Brexit success—if the roll-over trade deals with Japan and others can be described as such. And her views, bating the woke while seemingly on board with the levelling-up wheeze, are an appealing prospectus to the members. The question is whether this could work. It’s one thing to adopt a polarising culture-war position, another when the issue that gave it vitality—Brexit—is done.

The Tories and Johnson are in for a rougher time as we head into 2022, but returning to the by-election, there are also questions for Keir Starmer’s Labour. Dropping to third with just shy of ten percent after coming second in the seat since 1997 is ostensibly damning. But is it? The Lib Dems were able to position themselves as the tactical anti-Tory choice, and given the lack of effort Labour put in versus the Old Bexley by-election, it appears the leadership had written their chances off from the start. The electorate responded, and Labour voters made the switch to give Johnson a deserved bloody nose.

The problem Labour has is not so much one of voters going tactical, but the fact that it’s not seen as a viable vehicle of a similar tactical campaign—particularly in a seat where Labour was second placed for a quarter of a century. A similar pattern is repeated in local council by-elections. The Lib Dems and even the Greens do a better job of taking seats from the Tories than Labour does, suggesting they benefit from a greater degree of anti-Tory vote lending than the main opposition party. North Shropshire was a disaster for Johnson. It would be a stretch to use the same descriptor for Labour—but it was certainly a cause for concern.