A Vote That Did Not Exist: Favelas, Violence, and Change between Rounds in Brazil’s 2026 Presidential Election

In this paper, we examine Lula’s gains between rounds in Brazil’s 2026 presidential election. We hypothesise larger gains at polling places with a higher share of voters living in favelas. Using section returns and the 2022 Census, we estimate electorate composition at 3,478 polling places in Rio and São Paulo. Results support this hypothesis after controlling for income, violence and first-round results: the 10th–90th percentile difference is about one percentage point of the registered electorate. Favela proximity was associated with gains in São Paulo, while Flávio Bolsonaro gained less in more violent areas. The association between favela residence and Lula’s gains strengthened relative to 2022; across 23 cities, the increase was smaller on average and significant in only five. The 2026 association was larger where state governments elected in 2022 were allied with Bolsonaro. These exploratory findings suggest that state security policies may carry electoral costs for allied presidential candidates.