Recent polling from institutes including Quaest and AtlasIntel has positioned federal deputy Luciano Zucco (PL) ahead or in a technical tie with Juliana Brizola (PDT) in first-round voting intentions for the October 4 election, with Zucco favored in most simulated runoff scenarios against her or vice-governor Gabriel Souza (MDB). Zucco’s support has shown modest gains in September surveys amid a fragmented field that includes low-single-digit candidates such as Marcelo Maranata (PSDB). High shares of undecided voters and blank/null intentions continue to compress leads, yet the consistent polling edge for Zucco aligns with trader pricing that assigns him the highest implied probability. The first-round vote and any October 25 runoff will determine the winner under Brazil’s two-round system.