This paper analyses the differential behaviour of centre‑right electorates in Spain and Portugal in response to the rise of the radical right in both countries. Drawing on the contrast between the most recent Spanish general elections and the 2026 Portuguese presidential elections, it proposes the hypothesis that moderate centre‑right voters have operated under different strategic logics in each political system. In Portugal, a significant share of voters located in the moderate conservative space appears to have opted to support the Socialist candidate António José Seguro in the second round of the presidential election, prioritising the containment of Chega over ideological proximity to their own bloc. In Spain, by contrast, the high level of political polarisation seems to have favoured a stronger integration of Vox within the right‑wing bloc, allowing more intense vote transfers between the centre‑right and the radical right.

The central argument holds that the difference between the two cases cannot be explained solely by party supply or ideological proximity, but also by the degree of political and emotional polarisation present in each system.

Methodologically, the paper is conceived as a comparative study of two Iberian cases. It draws on two public opinion studies conducted in Spain and Portugal. The aim is to contribute to the debate on the relationship between polarisation, the reconfiguration of the centre‑right, and the normalisation of the radical right in European democracies. The comparison between Spain and Portugal allows us to explore the conditions under which moderate right‑wing voters act as a barrier against the radical right and the conditions under which they instead contribute to its incorporation within a competitive political bloc.