Guilherme Derrite (PP) holds the strongest position among candidates for first place in the October 4, 2026, São Paulo Senate election, where voters select two senators for eight-year terms. Recent late-September polls from Quaest, RealTime Big Data, and Datafolha show him leading or tied numerically in consolidated vote shares, often ahead of André do Prado (PL), Simone Tebet (PSB), and Marina Silva (Rede), though margins fall within sampling error. Derrite benefits from alignment with Governor Tarcísio de Freitas and state-level security messaging, while Tebet and Silva draw presidential backing. Ricardo Salles (Novo) exited the race days before the latest surveys. Low name recognition and high undecided rates persist across the field, keeping outcomes fluid until election day.