In a seismic shift that has reshaped Canada’s federal political landscape this week, a veteran Conservative Member of Parliament from Ontario has crossed the floor to join Prime Minister Mark Carney’s Liberal Party, bringing the ruling party just one seat away from securing a long-sought working majority in the House of Commons.
Marilyn Gladu, who represents the border riding of Sarnia-Lambton-Bkejwanong, made her party switch official this week, framing the decision as a response to her constituents’ demands for competent, forward-thinking governance focused on growing a more robust and economically independent Canada. Gladu’s defection marks the fifth time a sitting MP has abandoned their original party to join the Liberal caucus in just a matter of months, a string of moves that has rapidly eroded opposition numbers and left the Liberals on the cusp of a majority.
After Gladu’s switch, the Liberals currently hold 171 seats in the 338-seat House of Commons. Only one more seat is needed to hit the 172-seat threshold required to form a full majority government, a goal that is now within touching distance for Carney’s administration. The string of defections began earlier this year with three Conservative MPs – Matt Jeneroux of Alberta, Chris d’Entremont of Nova Scotia, and Michael Ma of Ontario – leaving the official opposition to join the Liberals. Most recently, last month saw Lori Idlout, the MP for Nunavut, depart the New Democratic Party to caucus with Carney’s government.
Carney embraced Gladu’s arrival in a public social media statement, framing the string of defections as a sign of growing confidence in his government’s agenda amid ongoing global economic volatility. “At a moment when the global economy faces unprecedented uncertainty, Canada’s success depends on turning our ambition into tangible progress and our existing strengths into long-term, sustained competitive advantage,” Carney wrote. “Marilyn Gladu brings exactly the kind of practical, results-focused leadership that this work demands, and I am thrilled to welcome her to our team.”
Not surprisingly, the move drew fierce pushback from Conservative Party leader Pierre Poilievre, who slammed the defection as part of what he called a underhanded power grab by Carney. Poilievre accused the prime minister of trying to accumulate a majority “through dirty backroom deals” rather than through a general election, and called on Gladu to trigger a by-election in her riding to let her constituents weigh in on her party switch. “The people of Sarnia-Lambton-Bkejwanong voted for a Conservative vision of a Canada that is affordable, safe, and strong at home – not for the costly, big-spending Liberal government that Gladu has now chosen to join,” Poilievre wrote in his own social media statement.
Gladu pushed back against that criticism in her public announcement, which included a video appearance alongside Carney, noting that her riding sits directly along the Canada-U.S. border, making economic resilience and national independence top priorities for her constituents. “My choice to join the Liberal caucus is the best decision for the priorities of our community, and most importantly, for the future of our entire country,” Gladu said. “We need a proven global leader with a clear plan to build a more resilient, more self-reliant Canada, and that is exactly what Mark Carney delivers.”