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Third Parties in Britain’s Upcoming General Election: How well can we expect them to perform?


Joseph Taylor

Friday, 15 March 2024

An analysis on the prospects of third parties in the upcoming general election.

Third Parties in Britain’s Upcoming General Election: How well can we expect them to perform?

Within the next 12 months, Britain will hold another General Election; its first in five years. A return to regularity following a series of snap elections in the second half of the 2010s. With the Conservative Party’s support being at an astounding low (polling 20% at time of writing this article), it is likely that Sunak’s government will hold off dissolving parliament for as long as possible unless his party experience a sudden spike in support. Whilst it is almost a certainty that the Conservatives will be replaced by Labour as a result of the 2.5 party system we have in the UK, this article takes a look into the 0.5 and how we can expect third parties to perform in the election. 

Britain’s general elections operate a first-past-the-post system by which a constituency is won by simple plurality (essentially, most votes wins) which favours the two largest parties in the country. This is because they have a huge amount of support nationally and can realistically contest most constituencies. Third parties are disadvantaged in that sense as their support tends to also be national but in lesser amounts. The Green Party for example received 865,707 votes nationally in the 2019 election but won just one seat, Brighton Pavilion, where they won 33,151 votes due to a higher concentration of support for the party there. The same can be said for parties such as the Liberal Democrats and Reform UK who win a relatively large share of the vote but lack the voter concentration to win a substantial number of seats. 

Having said that, some third parties in the UK benefit from First Past the Post. The Scottish National Party (SNP) and Plaid Cymru (PC) stand only in Scotland and Wales respectively and as such benefit from the electoral system in a similar way to the Conservatives and Labour. Their support is concentrated regionally and so they are able to win a decent number of seats. Plaid Cymru, for instance, won four seats in 2019 with just 153,265 votes in total. Less than 1/5 the number of votes of the Green Party but winning four times the seats. Likewise, the SNP won 48 seats with 1,242,380 votes compared to the Lib Dems’ 11 seats with 3,696,419 votes. 

The 2019 election was fought on the issue of Brexit, with the Conservatives’ promise of a swift exit attracting a large number of voters across the country. This most notably won them seats in the so called Red Wall, an area across the north of England which has traditionally been a Labour stronghold. Since Britain’s exit from the EU however, we have seen the Covid-19 pandemic, war in Ukraine and, most recently, the Israel-Palestine conflict. These events have resulted in economic decline for Britain and consequently a drop in support for the Conservatives. This therefore puts a lot of constituencies into the mix for non-Conservative parties to win. Whist many will undoubtably swing to Labour, there will be some gained by other parties.

And so, taking this into account, realistically, how many seats can we expect to be won by third parties in the next election? Well to start off, all 18 of Northern Ireland’s seats will be won by a party outside of the Conservatives and Labour due to the two major parties not contesting constituencies on the emerald island. The Liberal Democrats can potentially swing a large number of seats in the next election, having come a close second to the Conservatives in 2019 in a number of seats which would require only a small swing to win net time out. This however doesn’t factor in the surge in popularity experienced by the Labour Party who will likely have the swing to beat out both the Conservatives and Lib Dems in many of these seats. I predict they will win just under 40 seats in the upcoming election as it is likely anti-Conservative tactical voting will come into play and cause Labour voters to lend their vote to the Liberal Democrats in some marginal seats. The Green Party’s strategy for 2024 will focus on four constituencies: Brighton Pavilion, the one seat they currently hold; Bristol Central; Waveney Valley; and North Herefordshire. I predict that out of these, Brighton Pavilion and Bristol Central will see the Greens victorious; another two seats for a third party. Reform UK I can’t see winning any seats in the upcoming election. Whilst they are polling as the third most popular party at time of writing with 13% of the vote, the seats they are likely to do best in should all be won comfortably by Labour. There could potentially be a surprise in a constituency such as Barnsley North if Labour fails to reassure the electorate on the issue of immigration, however the election will almost certainly be fought on the economy due to the cost of living crisis putting many people’s finances into uncertainty, and I think that Reform will come second to Labour across the north as a result but the third largest vote share nationally. 

Whilst third parties will likely see a rise in seat share in England then, the opposite is likely to happen in Scotland. The SNP have seen a decline in the polls recently at the expense of Labour and will likely lose its strong grip over the nation as a result. I predict that the SNP will win about 20 seats in the election, a drop from the 48 they won in 2019. However, Wales is a different story. Plaid Cymru currently hold four seats, having won all four at the previous election. Of these four, only one is considered a marginal, Ceredigion Preseli, where the Conservatives require a 1.4% swing to win the seat. Although, it is very unlikely that the Conservatives will gain votes though and so I predict that PC will hold all four of their seats in the next election.

To summarise my predictions, I am expecting third parties to win around 80±5 seats in the general election. Whether this prediction is correct or not will depend on various factors such as changes in support for the two main parties as we approach the election, and the extent to which tactical voting will be used to ensure a Conservative defeat. However with likely no substantial change in the number of seats being won by third parties compared to 2019 (82), Britain’s 2.5 party system remains firm even despite the Conservatives polling at their lowest since the 70s.  

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