Boris Johnson is losing his grip on power. Only a third of those who voted Conservative in North Shropshire at the last election turned up to support his party in yesterday’s by-election. The supporters he could once rely on are leaving.

A combination of apathy, disgust, tactical voting and protest votes saw an historic 34% swing to the Liberal Democrats – the seventh-largest swing in any by-election since World War Two.

Yet this should have been solidly Conservative territory: a Leave-voting, rural shire seat of small, picture-postcard market towns, which has elected Tory MPs since 1904.

In fact, this was the 76th-safest Conservative seat in the country – meaning that another 288 seats won by the party in 2019 are now vulnerable to similar swings.

The problem for Johnson is that the coalition of Brexit supporters he forged is unravelling. At the last general election, in 2019, the prime minister won a thumping majority and smashed Labour heartlands by promising to “get Brexit done”. But with Brexit now completed, recent events have overtaken, with the government engulfed in sleaze scandals and criticisms of how it has handled the pandemic.

Political scientist Matt Goodwin – who normally talks up Johnson’s prospects – recently highlighted that more than half of Leave voters no longer align with the Conservatives. The result was seen in yesterday’s election: in a heavily Eurosceptic constituency, farmers who have suffered from the loss of EU funding ended up supporting the most pro-European of all the main political parties, while Europe itself was barely mentioned in the campaign.

The results are even worse than national polls suggest. Recent surveys say the Conservatives are trailing the Labour Party by around 5%-9%. By historic standards, that actually isn’t too bad for a mid-term government; when John Major was prime minister in the 1990s, his ratings trailed Labour’s by 25%. Against this backdrop, the loss of such a safe Tory seat is even more sensational.

The campaign

At the last election, the Conservatives won a solid 22,949 majority in North Shropshire, meaning that few punters yesterday were expecting a defeat of this magnitude.

Little attention was initially paid to Lib Dem claims of being on the brink of a breakthrough (this is, after all, what Lib Dems often claim, in almost every seat).

But it was clear that the wheels were falling off the Conservative campaign. Fury at the Downing Street parties was palpable. One Tory canvasser told me he had yet to meet anyone in the seat who wasn’t voting Lib Dem. He later corrected his statement, after he met a lone Tory voter – although it turned out this voter also happened to be the wine merchant for the local Conservative Association.

The Lib Dems, for their part, were keen to avoid any controversy. After her win was announced, the party’s new MP, Helen Morgan, was abruptly bundled away by aides, determined for her to avoid questions from journalists. The Conservative candidate wasn’t so lucky.

It is also important to remember why this by-election happened in the first place. The former Conservative MP Owen Paterson was due to receive a 30-day suspension from Parliament after a lobbying scandal, but Boris Johnson tried to tear up the rule book to save him. Paterson quit in the subsequent furore.

This by-election could quite easily have been avoided by the government, if it had simply followed the rules. And now, after the disastrous result, Conservative MPs will be furious.

Lib Dem resurgence?

A Lib Dem by-election resurgence often means ‘business as usual’ for British politics. Before the party’s decade-long drought of gains between 2006-16, it had often picked away at government seats during mid-term votes..

The Lib Dem leader, Ed Davey, will be hoping that this result might change the public’s perception of his party. It’s their fourth by-election gain in five years and, for a party that has been an electoral irrelevance for much of the past decade, they have started to look like winners again.

This is significant because insiders have told openDemocracy that one of the main reasons for losing support in past elections was that they no longer “looked like winners”.

And this is not just significant for the Lib Dems. After all, it was the collapse of the party’s support in 2015 that handed the Tories their first majority in 23 years. And it was the disappearance of the Lib Dem threat in Tory-facing seats that allowed the Tories to focus on winning traditionally Labour seats across England. After yesterday’s result, the Tories may struggle to go back to fighting on multiple fronts.

Labour’s dilemma

After the Conservatives, the biggest loser from this by-election is Labour. The party shed more than half of its vote share, from 22% to 10%, and was pushed into third place.

But the bigger problem for Labour is a more existential crisis. Rumours have circulated for some time that Labour and the Lib Dems have been angling for an election pact – an informal agreement to give each other a clear run when the other is a serious contender, short of standing down candidates. We may have seen this play out in North Shropshire, given that most of Labour’s shadow cabinet kept well clear and let the Lib Dems do their thing.

But any election pact requires goodwill from both parties and each needs to be able to claim some victories. Yet Labour made little headway in the Old Bexley and Sidcup by-election held earlier this month. Labour supporters may well ask what they get out of a pact: the party has more to gain at a general election, but it is the Lib Dems who look more likely to win by-election spoils before that.

Meanwhile, Labour’s by-election machine remains defensive, not offensive, and the party has consistently underperformed when it needed to break new ground. In fact, Labour has not gained a seat at a by-election for more than nine years.

This is not a good position for the main opposition party to be in. Even unsuccessful past leaders like Michael Foot managed to win a by-election gain for Labour, while a two-times general election loser like Neil Kinnock notched up five by-election wins.

Keir Starmer desperately needs a by-election win to show that victories are possible. But possible future votes in seats like Windsor do not seem promising. Indeed, it’s hard to think what a good prospect for Labour would look like.