PL leads the Brazil Chamber of Deputies market with 75.5% implied probability because it already holds the largest bloc after the recent party-switching window closed, expanding from 87 to 100 seats and solidifying its position ahead of the October 4, 2026 vote. Traders price in continued right-wing momentum tied to Jair Bolsonaro’s endorsement of his son Flávio and voter dissatisfaction with President Lula’s administration amid economic pressures. Other parties such as União Brasil trail at 10.5% due to smaller current caucuses and weaker polling trends. The race remains open to shifts from candidate withdrawals, coalition realignments, or late economic data, though PL’s structural advantage and base mobilization keep it the clear frontrunner in the wisdom-of-crowds assessment.