The rise of the radical right in Europe is often explained by the so-called 'modernization losers' theory. This research shows that, at least in the Region of Madrid (RoM), Vox's electoral breakthrough does not align with this theory. Using a comprehensive database of income variables and election outcomes at the census section level, this study employs vote transfer matrices estimated through ecological inference to identify the characteristics of RoM Vox voters in both general and regional elections from 2016 to 2023. Our results reveal that it is the upper-middle and right-middle classes who enabled Vox's emergence and growth. It is only later¿following the outbreak of the COVID-19 pandemic and the implementation of mobility restrictions in 2020¿that modernization losers began to join its electoral base. While the study primarily focuses on electoral supply, it also considers demand-side factors. The interaction between these elements, along with contextual influences, helps explain Vox's evolving support over the study period. Furthermore, this support is strongly shaped by the characteristics and discourse of the competing candidate from the traditional right.
