The 40 to 55 Channel of British Politics

Voting intentions in Britain were remarkably stable for the first half of 2025. The last time the polls were this stable was 10 years ago in the run up to the 2015 General Election.

What’s that I hear you say? Have I not noticed the surge in Reform’s vote share from 20% to 30%? I have but I’m focusing on the 40-55 Channel which has been the defining feature of voting intentions for nearly all of the last 15 years. Everything I see in 2025 tells me the 40-55 Channel will continue to define British politics all the way through to the next election by 2029. Perhaps I better explain what I’m talking about.

15 Years of Voting Intention Polls

The story of the polls since January 2010 can be seen in the chart below. I track the 9-poll rolling average of all polls published as recorded by Mark Pack who has systematically recorded every opinion poll published since 1945. The vertical bar for each month shows by how much the 9-poll rolling average has varied in each month. The line for Reform includes its predecessors of UKIP and the Brexit Party. Polls only started tracking UKIP and the Greens regularly after the 2012 local elections hence why I start the chart just before the 2010 general election.

The change in the fortunes of the parties since the end of June last year (4 days before the election) is extraordinary. The list below is the 9-poll rolling average as of 30th June 2025 with changes since 30th June 2024 shown in brackets split into two time periods. The first period (JD) is the change between the end of June 2024 and the end of December 2024, the second period (DJ) is the change between the end of December 2024 and the end of June 2025.

REF 28.1% (JD +5.8%, DJ +6.7% )
LAB 23.8% (JD -11.3%, DJ -4.2%)
CON 18.1% (JD +2.1%, DJ -6.3%)
LDM 14.0% (JD +0.9%, DJ +2.2% )
GRN 9.3% (JD +2.4%, DJ +1.2% )
OTH 6.7% (JD +0.1%, DJ +0.4%)

Bear in mind these are changes in the polls over 12 months, not since the election last year. The track record of polls is not great and the error in the Conservative lead over Labour in last year’s general election was the 2nd largest on record. That being said, the above figures & chart speak of widespread political fragmentation and major voter churn.

Voting Intentions are stable in 2025

But what if I redo the list as below…

CON+REF 46.2% (JD +7.9%, DJ +0.3%)
LAB+LDM+GRN 47.1% (JD -8.0%, DJ -0.8% )
OTH 6.7% (JD +0.1%, DJ +0.4%)

… and replot the chart accordingly?

If I label the sum of CON+REF as The Right and the sum of LAB+LDM+GRN as The Left, I don’t think I would be misdescribing British politics. Over the last 6 months, the standard deviation of the 9-poll rolling averages for the Right & Left separately has been under 1%. The last time that happened was in the 6 months prior to the 2015 general election.

This is why I say voting intentions have been remarkably stable so far in 2025 when viewed through the lens of The Right and The Left. All the turbulence between the parties in 2025 has been taking place within the two wings of British politics.

The 40-55 Channel

This is not the first time I’ve talked about The Right and The Left. I used the same concept to make my successful forecast of the 2019 general election and wrote about this in more depth in May 2021. The difference back then is I used the descriptors Leave Alliance (LVA) and Remain Consortium (RMC) instead. I think Brexit related descriptors are now outdated but the underlying concept is not. If I zoom in on the chart above, I can identify the 40-55 Channel which has been the main determinant of British politics for the last 15 years.

The Right and The Left vote shares have fluctuated between 40% and 55% in voting intention polls since 2012 (when polls started tracking UKIP and the Greens) and more likely since the 2010 general election. This is what I call the 40-55 Channel.

For a 30 month period between January 2022 and June 2024, it looked like the 40-55 Channel had been consigned to history. However, the general election last year showed it had not gone away and voting intention trends since has only strengthened its relevance. I predict the 40-55 Channel will continue to define British politics all the way through to the next election. Further turbulence and drama within The Right and The Left is likely to be the norm for the next few years but I think the top line pattern of the last 15 years is here to stay.

The 30 Months Blackout

Why did the 40-55 Channel disappear for the 2nd half of the 2019 to 2024 parliament? My explanation is two names; Boris Johnson and Nigel Farage.

After the 2019 general election and with Britain’s exit from the European Union secured, Nigel Farage chose to step away from British politics. The Brexit Party mutated into Reform and Richard Tice took over the leadership though Farage continued to own 53% of the party’s shares. Throughout 2020 & 2021, Reform averaged 3% in the polls and Tice’s profile in British politics was low.

Boris Johnson was the undisputed leader of the Right to the extent the Conservatives won Hartlepool from Labour in May 2021 in a by-election. For any government to make a gain from the opposition in a by-election is extraordinary, to do so in what had always been part of Labour’s Red Wall was unprecedented. However, by the end of 2021, Johnson was blamed for the loss of the safe Conservative seat North Shropshire due to the Owen Patterson affair. That began 8 months of political turbulence within the Conservative government which ultimately led to his resignation as Prime Minister.

Throughout the 2010s, Nigel Farage had an outsized influence on British politics and was always well placed to take advantage of any voter dissatisfaction with the Conservative party in particular. He led UKIP in 2014 and the Brexit Party in 2019 to victory in the EU elections, the only two national elections since 1906 where neither the Conservatives or Labour have topped the poll. But by stepping away in 2020, he was absent in late 2021 when Conservative voters started to desert the party. Tice was unable to attract these voters and by October 2023, Reform was only polling 6% even though the Conservatives were already down to 27%. Instead, Conservative voters temporarily defected to Labour and appeared to consign the 40-55 Channel to history.

It was at this point Reform started to trend up in the polls and when the 2024 general election called, Farage eventually decided to re-enter the fray. Since then, his influence on British politics has returned and Nigel Farage is the main reason why I say the 30 month blackout was a mirage and the 40-55 Channel is here to stay till the next election.

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