Brazil votes for two Senate seats in October election

In Brazil's 2024 general election, voters will select two senators per state and the Federal District, filling 54 of the 81 Senate seats. The other 27 seats, elected in 2022, remain occupied because senators serve eight‑year terms with staggered renewal.

On election day (4 October), the electronic ballot requires each voter to cast two separate votes for different candidates. Voters must enter the three‑digit candidate number; duplicate numbers or votes for candidates from other states are rejected, with only the first entry counted. Party lists are not used for Senate voting.

The system has historically caused many "incomplete votes," where electors leave one of the two slots blank or cast a null vote. In the 2018 election, about 63 million such votes were recorded. Analysts note that the Senate's unique powers—approving authorities, loans, and foreign policy matters—bring heightened attention to its composition amid a polarized political environment. The election does not include a second round; the two candidates with the most votes in each jurisdiction win the seats.