Brazil electoral polling: Methodology shifts and 2026 data aggregation

The Inteligov platform has updated its consolidated tracking of voting intentions for the 2026 Brazilian elections, aggregating 470 surveys registered with the Superior Electoral Court (TSE). The system monitors candidates across 27 states, including São Paulo, Rio de Janeiro, and Minas Gerais. To calculate a weighted moving average, the platform applies specific statistical weights: in-person home surveys receive full weight, while telephone or internet surveys have their influence reduced by 30% to 45%. Additionally, the weight of data is reduced by 25% for every two weeks that pass since the field collection.

In Minas Gerais, questions have been raised regarding the methodology of Instituto Veritá. A comparison of three consecutive surveys conducted by the institute in May, August, and September revealed significant changes in statistical parameters for education and income. Specifically, the proportion of the sample categorized as having completed high school rose from 64.1% in May to 78.4% in September, while the proportion with higher education fell from 35.9% to 21.6%. The institute has not cited the specific criteria used for these shifts in weighting.