The Pact Trap
Why intra-bloc alliances remain unlikely
One of the recurring questions I hear now around UK politics is about whether the left and right blocs will come together through pacts. It is a sensible suggestion. First-past-the-post is deeply suboptimal for both voters and parties in a fragmented electorate. Splitting your own bloc can easily concede ground to the other one, even if you outnumber them overall. This was the fear among the left in Gorton and Denton, for example, that left-leaning voters would split evenly between Labour and the Greens, allowing Reform to win with maybe a third of the poll. Both blocs have the same issue in Makerfield, with Labour worried about leakage to the Greens and Reform increasingly concerned that Restore will spoil the right vote.
In these circumstances, a pact makes a lot of rational sense. Agreeing with the other parties in your bloc to divvy up the country can maximise your chance of winning overall. Such a “progressive alliance” has long been mooted on the left. The idea is that rather than competing, Labour, SNP, Plaid, Greens, and maybe even the Lib Dems could formally coordinate to play to their strengths and lock out the right. Now, some on the right are mooting the same sort of deal, especially an allegiance between the Conservatives and Reform, to avoid splitting each other’s vote.
The current electoral situation should make deals more likely. Politics is fragmented like never before, and there is a huge benefit to be gained by whichever bloc unites first. Yet such pacts remain unlikely. However rational the polling numbers suggest that they might be, they remain difficult to form in practice. This is partly because of the unpredictable behaviour of voters, but also because of the positions the parties themselves take, blind to their own weaknesses and unwilling to cut deals at the prevailing market price. As ever, difficult politics often override impeccable logic.
The first problem that pacts run into is that they require political parties to be brutally honest about where they sit in the batting order. Both Labour and the Conservatives are used to being the winning party across hundreds of seats. Whilst they understand you write off ones where your vote share never ticks above 20%, those aren’t the ones that matter in an electoral pact. The difficult decisions lie in the seats where you think you have a decent chance of winning.
This issue is sharpened by the electoral shift since the last election. Both historic main parties were dominant in their bloc in 2024. Now they are not. That means there is a huge disparity between the seats they currently hold and those they might win today. Doing a deal with their intra-block opposition would mean giving up seats they already hold or that they fancy their chances of winning. Accepting this is difficult for any party used to being the predator rather than the prey, especially when it means abandoning sitting MPs. Sure, there’s a chance you could persuade the Conservatives to let you have a free run at Wigan, but they would be unwilling to include Broxbourne in a deal unless they really felt the squeeze. Likewise, Labour is very unlikely to surrender current MPs to an impending Green wave.
The same dynamic works in reverse for the insurgent parties. They know their power from looking at the polling and will want to press their advantage. Neither Reform nor Greens will be happy with scraps when they have a sense that they can eat the other party’s lunch. The chance to gain dozens (for Polanski) or hundreds (for Farage) of MPs is worth more to you than anything the more traditionally powerful party is willing to give you. There is a mismatch of expectations largely driven by the irrationality of the incumbent parties. The only real pact that has ever emerged, that between Conservatives and the Brexit Party in 2019, was largely the result of the latter realising it would never achieve more than being a spoiler for its own political objectives.
Underlying this is the broader issue – the voters get a say. The by-elections and local elections in this parliament have already demonstrated that voters are efficient at tactically sorting themselves around a preferred outcome. In both Gorton and Caerphilly, the left bloc you’d expect to dominate the seat allocated itself effectively, punished Labour and avoided a Reform victory. Likewise, Farage’s party basically swallowed the old Conservative vote in these seats whole, with the party crashing to deposit-losing levels. Similar sorting can be seen at the local level in many places through the council elections this year and last. The truth is that the parties don’t really need to work to optimise the bloc votes; in most places, the voters can do it.
This dynamic also shows the limits of what is possible. Much to the consternation of observers, voting blocs are less coherent than you might expect. The electorate is not made of pieces of Lego that can be slotted together into whatever arrangement party chiefs prefer. A bloc is often less than the sum of its parts, and people have odd second preferences or none. It cannot be assumed that Conservative voters will prefer a Farage-led government to a Labour-led one, for example. Indeed, at the current state of play, you would expect the voters who are left voting Tory to be the ones least amenable to backing Reform – otherwise they would likely have switched already.
The exact nature of the fragmentation also leans against the formation of pacts. Our electoral contests are no longer simple left vs right fights. They instead resemble a series of regional contests between incumbents and the strongest opposition party. In urban centres, for example, there is a choice between Labour and Green. In parts of outer London and very rural constituencies, the main choice is between Reform and the Conservatives. In towns and suburban seats, it is mostly Lab vs Ref, and of course, the independence parties play a major role in Scotland and Wales. A national pact sends a message which clashes with this. The Conservatives doing a deal with Reform in the north would further hamper them in contests against the Lib Dems; likewise, Labour looking allied with the Greens would motivate Reform voters against them in places like Doncaster. A pact designed to win everywhere ends up being the wrong message almost everywhere.
The geography problem is compounded by something even more fundamental: any pact worth having requires parties to agree on what they would actually do with power. This is a huge problem to coordinate, as parties will both want to maximise their individual chances of winning and those within the bloc. They will want an offering that pleases their electorate, but also reaches out to floating voters, often in very different contests. A Lab-Green pact, for example, would need an immigration policy that is competitive in Runcorn and Rusholme – and if that existed or was easy to find, our politics probably wouldn’t be fragmenting.
Ultimately, if pacts were easy, there wouldn’t be any need for them. Even within broad electoral blocs, there is disagreement over policy, and appeals are made to different types of voters. These have developed because it is becoming increasingly hard to offer a successful national platform. But the dynamics between these parties make conciliation even more difficult. They themselves want to fight for dominance within the bloc, both to maximise their own power and because of cultural and identity differences. Many Green voters *want* to stick it to the Labour Party, and activists even more so. Reform aims to replace the Conservatives, even if the latter haven’t reckoned with it yet.
Voters are already performing the sorting that electoral pacts try to manage, and appear to be doing it effectively. Parties are unlikely to agree on the terms when this has created a mismatch between their incumbent power and the threat posed by the next election. Quite simply, the two historic powers hold too many seats they would be reluctant to give up, and the insurgent ones see the gains for pressing on as too valuable to be bought off. Finding a mutually agreed price for the pact is highly improbable. Whatever sense it may make on paper, the blocs officially teaming up is fraught with difficulty and a doubtful prospect. First past the post might be unsuited to our political fragmentation, but until the structures of UK politics adjust to this new dynamic, each side is likely to be trapped in this sub-optimal game-playing.
