Spanish Electoral System Historically Skewed to Favor Right-Wing Parties

Spain's electoral system, primarily shaped by the Organic Law of the General Electoral Regime (LOREG) in 1985 and grounded in the 1978 Constitution, reflects an intentional design that benefits right-wing parties, particularly the former ruling Union of Democratic Center (UCD). The Constitution does not explicitly detail the electoral mechanisms, leaving significant flexibility that LOREG exploited to favor the political elite at the time. This system enabled the UCD to secure parliamentary majorities with only 30-33% of the vote by strategically reducing the number of seats in smaller provinces, especially lowering some districts from four to two seats. The overrepresentation of smaller, often rural districts tends to advantage conservative parties, contributing to what recent studies show as one of the highest levels of conservative bias in electoral systems globally.

This bias manifests distinctly across district sizes—the smallest districts enhance major party advantages, notably the right, while larger districts can have more proportional results. Such design choices have had lasting effects on Spain's political landscape, influencing the balance of power in both national and regional levels, including Catalonia.

Additionally, political parties in Spain undergo frequent branding changes, although less often than in some European countries. An example noted is the recent rebranding of Esquerra Republicana de Catalunya, reflecting common practices in party politics.

This deliberate electoral engineering raises important questions about representativeness and fairness in Spanish democracy, as the system continues to favor conservative forces due to structural imbalances established decades ago.