King's College London

Most European countries use a proportional electoral system where the territory is divided between large districts, usually cities, and small districts, usually small towns, or villages. This combined with an historic ideological divide between left-wing cities and right-wing countryside means there is a bias towards right-wing political parties.

Mechanically, right-wing parties receive more seats than left-wing parties by the simple fact of being more popular in small districts where large parties are advantaged.

According to new research, this bias becomes more significant because of a reluctance among left-leaning voters to abandon their preferred party in favour of a strategic vote compared to right-leaning voters. This is due to the tendency of left-wing voters to feel more emotionally attached to their favourite party, which make them more reluctant to abandon it. Right-wing voters on the other hand show much less reluctance to give up on a party they perceive as being unlikely to winBy doing so, the make sure their maximize their chance of influencing the outcome at elections in the short term.

The findings were revealed in a new paper, The psychological partisan effect of electoral systems: How ideology correlates with strategic voting, co-authored by Professor Damiel Bol and PhD candidates Andrew Hunter, who graduated from King’s in the summer, and Gabriela Aguirre Fernandez, from the Department of Political Economy.

The researchers studied data from the Comparative Study of Electoral Systems which covered 44 elections in 10 countries that used districted proportional representation in western Europe between 1996 and 2019.

They said: “Our findings show that right-wing voters seem to be more likely to make their vote count by avoiding parties that are unlikely to win a seat in their district. By doing so, they seem to adopt a strategy to maximize their chances to influence the electoral outcome in the short term.”

“By contrast, left-wing voters seem to be more likely to waste their vote by supporting parties that have little chance of winning a seat in their district. Note, however, that this loyalty vote might have some positive spillover effects in the future, for example by signalling to other parties or the electorate at large that their favourite party has supporters in the district.”

“Yet, it is also true that the reluctance to vote strategically does not contribute to the representation of their political preference in parliament in the short term.”