by Chris Curtis
Friday, 18
June 2021
Explainer
11:56

Here’s what the Amersham by-election doesn’t mean

A weird result may not tell us much about the national picture
by Chris Curtis
Lib Dem Sarah Green is the first non-Conservative MP since the constituency was formed. Credit: Getty

One of the big trends in polling over the past decade is that voters are becoming less loyal to political parties. Rather than faithfully dragging themselves to the polling station to vote for their preferred team, greater numbers than ever are taking a “Compare the Market” approach to elections. 

Analysis by the British Election Study Team October 2019 showed that “the 2015 and 2017 general elections were the most volatile we have seen in modern times” driven by “a long-term trend of partisan dealignment (weakening party identification) amongst voters.”

And it is this drop in party loyalty which is making British politics a lot weirder.

During 2019 we also saw extreme movements in support for political parties with the Conservatives falling to 17% in the polls as their voters bled away to the Brexit party. Just months later they bounced back to a landslide victory, winning seats across the Midlands and the North from voters who were once loyal to the Labour Party.

This weirdness is playing out on a local level as well as a national one, with last night’s Chesham and Amersham by-election the most recent example. If the result had followed national trends, Boris Johnson would already be halfway up the Metropolitan line to celebrate his party’s increased majority, after the Lib Dems fell into third. 

Instead, Ed Davey’s party leveraged local factors, most notably planning reform and High Speed Two, to pull off a shocking 25-point swing against the incumbents.

This isn’t the first-time local factors have mattered in politics, and it isn’t the first time we have seen a weird by-election result. But the fact that such dramatic results are happening on such a frequent basis is undoubtedly caused by this decline in party loyalty. The less loyal voters are to the Tories, the more open they will be to Lib Dem arguments around planning and High Speed Two.

Just like declining loyalty towards the Labour Party in Hartlepool meant voters were more open to Conservative arguments on their levelling up agenda.

The conversation now turns to what this means for the Conservatives. This decline in party allegiance means there are now no voter blocks that parties can take for granted. Therefore, there will always be a risk that what happened to Labour in the “Red Wall” could also happen to the Conservatives across the South. 

But I would still be wary about making any confident predictions. Just because a voter group is less loyal, doesn’t mean they will inevitably leave you. And the national polls still show the Tories are still riding high among all their key voter groups, with good approval ratings for Boris Johnson off the back of the successful vaccine rollout.

The only thing we can really be confident about is that politics is going to continue to produce a lot more weirdness.

Chris Curtis is a senior research manager at Opinium.

Join the discussion


  • The electorate here has now learnt it can pull politicians and the major parties around like marionettes. The kicker was the Euro elections during the dog days of the Brexit impasse at Westminster in 2019. We, the electorate joyfully decided to give both major parties a good kicking, and the Tories got their lowest ever vote share, basically doing for May, with both main parties but especially the Tories facing an existential threat. In typical Tory fashion, the Conservatives learnt the lessons fast, ditched May, and silenced their Europhilic wing. Labour buried it’s head in the sand and is still paying the price.

    And it seems to me the traditional perception, that politicians are the puppet masters manipulating the minds of us plebs with cunning narratives, is no longer valid. It is the other way round – politicians are projections of groundroots groundswells of hopes, fears, wishes, desires, anxieties; the leaders themselves buffeted by the wants of the mass of people who essentially created them. Like Brian from Life of Brian.

  • This seat is a poison chalice. On the one hand LibDems got support from long-term locals who don’t want any building – HS2, housing, or otherwise – in their backyard.
    And the rest of the support was from the younger ‘metropolitan liberal’ set fleeing London, who want places to live.

  • Yes. I would add that plenty of woke damage can be orchestrated at local levels too – unions, councils, well-meaning do-gooders.

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