**Nathalie Roy holds a clear lead in the Montarville riding at 68.5% implied probability, ahead of Jean-François Cloutier at 32.5% and other named candidates or “Other” at 50% or lower.** As the long-serving incumbent Coalition avenir Québec (CAQ) MNA and current President of the National Assembly, Roy benefits from name recognition and a proven track record in the Rive-Sud riding, which she has represented since 2012 and won with 45.9% of the vote in 2022. The October 5, 2026, general election was called on August 27 after the dissolution of the legislature, with nominations closing September 17. Roy’s mid-August confirmation that she would seek a fifth term, paired with projections from 338Canada and Qc125 showing the CAQ ahead on the new electoral map, has anchored trader expectations. Cloutier, the Parti québécois journalist candidate, represents the main opposition challenge in a riding where the CAQ has maintained consistent strength, though the broader provincial race remains competitive. No late-breaking local developments have shifted the balance as of early September.