Guilherme Derrite leads the São Paulo Senate race for first place in recent polling, with Quaest and RealTime Big Data placing him ahead numerically at 22-25% in first-preference scenarios, ahead of André do Prado, Marina Silva, and Simone Tebet in the low-to-mid teens. His position as former state public security secretary and alignment with Governor Tarcísio de Freitas' coalition has driven gains in the final weeks. Ricardo Salles' withdrawal on September 28 and endorsement of the conservative slate further consolidated support behind Derrite and do Prado. With election day on October 4 and large blocs of undecided voters, the market reflects trader consensus on Derrite's frontrunner status for the top spot amid an otherwise competitive field for the two available seats.