TORONTO (AP) — Canadian Prime Minister Justin Trudeau’s Liberal party has suffered a major upset in a special election for a Toronto district it has held for three decades, raising doubts about Trudeau’s leadership ahead of next year’s general election.

Elections Canada reported the opposition Conservative candidate winning the Toronto-St. Paul’s district by almost 600 votes, 42.1% over the Liberal candidate’s 40.5% with all 192 polling stations reporting. The Canadian Broadcasting Corporation declared Conservative Don Stewart the winner early Tuesday.

The Liberals had held Toronto-St. Paul’s since 1993. It is one of 338 seats in Canada’s House of Commons.

Losing in Canada’s largest city, a traditional Liberal stronghold, does not bode well for Trudeau ahead of the election expected in the fall of 2025.

“Justin’s position is seriously weakened inside the party,” Canadian historian Robert Bothwell said.

Bothwell said there had been solidarity with Trudeau’s leadership, noting some have just left the government rather than publicly grumble, but he expects comments now.

“The Liberals poured, and were seen to pour, everything they had into this one,” Bothwell said. “Bringing ministers down and mobilizing office staffs from Ottawa signaled desperation.”

Trudeau has said he intends to lead the party into the next election. The Trudeau Liberals have been in power since 2015 but are trailing badly in the polls amid concerns over the cost of living.

“There is a message that our voters would like to send Mr. Trudeau, and that’s one of change,” said Stewart, the Conservative candidate, said before results came in.

Trudeau reasserted the country’s liberal identity in 2015 after almost 10 years of Conservative rule. His legacy includes opening the doors wide to immigration. He also legalized cannabis and brought in a carbon tax to fight climate change.

Trudeau’s father, Pierre Trudeau, swept to power in 1968 on a wave of “Trudeaumania” and led Canada for almost 16 years.