The Member of Parliament from Sarnia—Lambton—Bkejwanong, Marilyn Gladu, is crossing the floor to join the Liberals, making the government one short of a majority.
Gladu said, in a statement, she is joining Prime Minister Mark Carney as she believes it is “the best thing for our community’s priorities and for our country.”
She is now the fifth MP to join the Liberals since the 2025 election and the fourth Conservative.
Chris d’Entremont, Michael Ma and Matt Jeneroux all left the Conservatives to join the Liberals between November 2025 and February 2026. Nunavut MP Lori Idlout left the NDP in March.
The move comes ahead of three byelections this Monday. If the Liberals win one of three seats, they will officially have a majority government.
The ridings of Scarborough Southwest and University—Rosedale were held by former cabinet ministers Bill Blair and Chrystia Freeland, respectively for over a decade.
“I’ve been watching the Prime Minister since he was elected, and, the big things that he is driving, nation-building projects, diversifying our trade, bolstering our defense, plans to address criminality and build more homes, these are all the things that Canadians want,” Gladu later said when speaking alongside Carney.
“He’s invited me to bring my experience, my talents, and my views into the large Liberal tent, and I think that will have a better effect inside than it will outside.”
Carney also released a statement welcoming Gladu to the Liberal party.
“Marilyn brings the practical, results-driven leadership this effort demands. Having spent decades of her career in engineering and international business, she understands what it takes to create good jobs, strengthen supply chains, and ensure Canadian industry can compete in a rapidly changing global economy,” read his statement.
Gladu was first elected in 2015 election and has been re-elected three times.
In her statement, Gladu called said her district of Sarnia—Lambton—Bkejwanong “always a bellwether riding.” It was last held by the Liberals from 1993 to 2006 and has been held by the Conservatives since then.
She ran for the Tory leadership in 2020, after Andrew Scheer stepped down, but did not meet the qualifications to be on the ballot. The party chose Erin O’Toole as its leader that year.
With files from the Canadian Press