PQ Momentum Grows After Win in Quebec’s Arthabaska Byelection

PQ candidate Alex Boissonneault celebrates at an election party during a byelection in Quebec’s Arthabaska riding, in Victoriaville, Que., on Aug. 11, 2025. The Canadian Press/Christopher Katsarov

The Parti Québécois (PQ) has secured its third successive byelection win in Quebec, solidifying the momentum of the sovereigntist party as it approaches the 2026 provincial election.

The PQ victory by former Radio-Canada journalist Alex Boissonneault in the riding of Arthabaska on Aug. 11 is a setback for Premier François Legault’s ruling Coalition Avenir Québec (CAQ) party, which had held the seat since 2012.

Boissonneault defeated Quebec Conservative Leader Éric Duhaime, securing more than 46 percent of the vote, while Duhaime came in second with 35 percent support.

CAQ candidate Keven Brasseur placed fourth, with just 7 percent of the vote, behind Quebec Liberal Party candidate Chantale Marchand, who won 9 percent support.

“Tonight, we have achieved an extraordinary feat,” Boissonneault told supporters who gathered at a Victoriaville microbrewery after the Aug. 11 vote. “We have just reclaimed our magnificent corner of the country.”

Boissonneault, who was born and raised in the riding, ran on a commitment to reinstate what he called a fractured “social contract” that results in Quebecers paying higher taxes without receiving proportionate benefits in return.

“How many people have told me door to door that they no longer accept paying taxes and waiting hours in emergency rooms, or being unable to access a doctor, or unable to find a daycare space for their child,” he asked.

Boissonneault will now take his place in Quebec’s National Assembly. He is the third PQ politician to do that via byelection in the past few years.

The sovereigntist party achieved victory in Jean-Talon in 2023 and in Terrebonne earlier this year. The PQ currently ranks fourth in seat count within the province’s legislature, yet it has maintained a leading position in the polls for nearly two years.

“Tonight, the people of Arthabaska-L’Érable join those of Jean-Talon and Terrebonne in sending a clear message to this government: enough with the back-of-the-envelope projects, enough with the shameless waste of public funds, enough with going around in circles waiting for changes that never come,” Boissonneault said.

Political Setback

Prior to Boissonneault’s victory, the CAQ had held the riding for more than a decade. CAQ candidate Éric Lefebvre won the seat with 52 percent of the vote in the 2022 general election.

Premier Legault conceded defeat shortly after 9 p.m., prior to the official announcement of the winner. He said he took “full responsibility” for the loss, speaking during a Victoriaville press conference alongside CAQ candidate Brasseur.

Legault noted that setbacks at Northvolt and the Société de l’assurance automobile du Québec (SAAQclic) scandal have taken a toll on the public’s perceptions of his party. Both have resulted in hundreds of millions of dollars lost for the province.

The Quebec government invested $270 million in battery-maker Northvolt’s Swedish parent company before the company filed for bankruptcy in Europe earlier this year, resulting in a loss of investment for the province.

The province also lost money on its digital modernization of Quebec’s auto insurance corporation, the SAAQclic. A public inquiry was launched earlier this year after it was discovered the project went half a billion dollars over budget.

“In the coming weeks, we’ll take a hard look in the mirror, fully accept Quebecers’ disappointment, and make changes,” Legault said.

Duhaime also addressed his supporters after his loss.

“We missed a historic opportunity to correct the worst democratic distortion in the history of Quebec,” the Conservative leader told supporters gathered in a Victoriaville restaurant. “But we succeeded in one thing: showing that, in French-speaking Quebec, there is an opposition to the Parti Québécois, and it’s the Conservative Party.”

Duhaime noted that despite the loss, the Quebec Conservatives have increased their support, saying that the party took just 25 percent of the vote in Arthabaska in 2022, compared to this year’s 35 percent.

Boissonneault will need to return to the campaign trail next year to keep his seat, as the upcoming general election is set for October 2026.

The PQ has maintained a leading position in the polls since late 2023. Party leader Paul St-Pierre Plamondon said last week that Boissonneault would be assigned “important responsibilities” in a prospective PQ government, adding that he possesses the necessary qualities to serve as a minister.

The Canadian Press contributed to this report.