Politics: Do voters primarily act rationally, or are they guided more by identity and emotion?

Note: The following article was written by Zain Khwaja L6B (20khwajaz@students.watfordboys.org)

If voters were rational, turnout would be closer to 0.

This reflects the view of Anthony Downs, an American economist, who argued that rational individuals vote only when the expected personal benefit outweighs the costs of participation, and when their individual ballot could realistically alter the outcome. Downs proposed the “calculus of voting” in 1957, a formula intended to quantify a personal assessment of the utility of voting:

R = (P × B) – C

Here, R is the reward from voting, P is the probability of being decisive, B is the benefit if one’s preferred candidate wins, and C is the cost of participation. Therefore, in elections with large turnouts, it is almost always irrational to vote from Downs’s point of view. This is because the probability of one’s vote being decisive is basically close to zero. If P ≈ 0, the formula reduces to –C, meaning voting only really produces a cost.

There is cogency to this conclusion when applying the Downsian framework to UK politics. In both 2001 and 2024, days before the respective general elections, Labour was ahead by around 15–20% in opinion polls. These elections also had the two lowest UK general election turnouts in the past 100 years, with 59.4% in 2001 and 59.7% in 2024. Here, Downs’s “calculus of voting” does seem to have a degree of accuracy. In such elections, where a party’s win was almost certainly guaranteed, the personal reward from voting would have been small regardless of partisan alignment. It would have been “irrational” to vote, which helps explain the low turnout in 2001 and 2024.

Yet this raises another question: why did around 59% of the electorate still vote in both elections?

To answer this, it is useful to focus on why opposition voters still supported Labour’s main opposition, the Conservatives, despite the pre-judgement shown in polls. In YouGov surveys from March 2024, 37% more voters viewed Labour as “very close” or “fairly close” to the working class compared to the Conservatives. This offers a reason for apparently irrational voting: it may not be out of hope, but rather fear. Conservative voters may have perceived a Labour victory as contrary to their economic interests, given Labour’s policy reputation and class appeal. So turnout can be seen not as irrational in a simple sense, but as consistent with identity-driven and group-interest voting, where voters participate to defend their social and economic position.

This can also be seen with culture and religion. In the 2024 United States presidential election, there were significant changes in the party choices of the country’s Muslim population. The two-decade run of Muslim support for the Democrats, forged partly from the partisan realignment after the September 11 attacks, had been badly damaged. In Michigan, a pivotal swing state with the largest proportion of Muslim and Arab-Americans out of the 50 states, Democrat nominee Kamala Harris received 22,000 fewer votes in 2024 than Joe Biden had received in 2020 across the state’s most heavily Muslim and Arab-American cities. In 2024, 61% of Muslim voters in Georgia, Pennsylvania and Michigan listed the Gaza War as their top priority, according to the 2025 ISPU American Muslim Poll.

This suggests Harris’s underestimation of the importance of expressing support for Palestinian self-determination until the closing stages of the campaign may have contributed to the sharp drop in Democrat support from Muslim voters. Although the shift in the Muslim vote may have proved electorally meaningful because of the Democrat loss, at the individual level it remained behaviour that Downs would still deem “irrational”. A single Muslim voter in Michigan was still not realistically going to alter the entire election result by themselves. However, their vote makes far more sense when seen through identity, emotion and moral concern rather than narrow self-interest.

Referring back to the Downsian model of rationality, which defines rational behaviour as a self-interested calculation of personal costs and benefits, these decisions cannot be fully explained. Ideas of positive distinctiveness, where individuals and groups see a clear disagreement in opinions on major issues, such as the Gaza War, highlight the role of emotional and identity-based factors. For both Conservative voters in the UK and Muslim voters in the US, voting choices reveal how support based on class, tradition, religion, culture or group identity can outweigh the tiny predicted self-benefit of voting in most cases.

This suggests that such choices are not rational in the Downsian sense, but instead demonstrate how identity and emotion drive behaviour in ways that traditional rational choice models cannot fully capture. This idea of expressive or identity-based rationality exposes a flaw in Downs’s model, which was later revised by Riker and Ordeshook with the addition of D, representing civic duty, identity and emotion:

R = (P × B) – C + D

This offers what empirical evidence suggests is a more useful and sustainable formula for voting rationality. It does not necessarily show that voters are irrational altogether. Instead, it shows that rationality in politics cannot just be measured through individual cost-benefit calculation. People vote because it says something about who they are, what they fear, what they value, and which group they feel connected to.

It is also useful to consider party appeal rather than only personal voter choice. Downs argued that rational parties must converge on the centre ground to maximise electoral support. This has historically been borne out in British politics, with Labour and the Conservatives often becoming increasingly similar in policies and manifestos, focusing heavily on the centre vote and avoiding extremist policies. However, the rise of Reform to the top of the opinion polls, leading by 12% as of September 2025 according to Ipsos, appears to contradict Downs. Reform has gained support not by using centrist compromise, but by focusing on identity-based and emotional appeals.

If their rise continues and their mass support is preserved, the definition of the “centre” itself may be reshaped, forcing parties to remould their ideological appeal to match Reform’s more radical nature. Reform’s present success shows that identity and emotion can overturn rational centrism in the short term. However, if Reform’s support lasts, then what currently appears irrational or emotional may eventually become electorally rational for other parties to copy. The centre may simply be redrawn, meaning Reform-centric appeal becomes the new focus for parties.

This suggests that rationality in politics is path-dependent. Identity-driven “irrational” shocks in politics can redefine future rationality, ultimately rewriting rational choice itself.

Overall, voters are not primarily rational in the narrow Downsian sense. If they were, turnout would be far lower, especially in elections where the result seems predictable. However, this does not mean voters are entirely irrational. Rather, voters often act according to a wider form of rationality shaped by identity, emotion, civic duty and group loyalty. Downs’s model is useful in showing why turnout is theoretically puzzling, but it is too narrow to explain how voters actually behave. The evidence from UK turnout, Conservative voting, Muslim American voting behaviour and Reform’s rise suggests that identity and emotion are not just minor influences on voting. They are often the main reason people vote at all.