But the minority government will hang on to two of the five seats it had on the line Thursday in the five provincial byelections: Scarborough-Guildwood and former premier Dalton McGuinty's old riding of Ottawa South.
McGuinty's former assistant, John Fraser, held on to the seat despite a tough race with Tory Matt Young.
It was a close three-way race in Scarborough, but Liberal Mitzie Hunter surged ahead of the Conservatives and New Democrats, who battled for second place.
But they lost Windsor-Tecumseh and London West to the New Democrats and fell behind the Progressive Conservatives in Etobicoke Lakeshore.
Foe-turned-friend union leader Ken Coran, the Liberals' star candidate in London, finished a distant third to NDP victor Peggy Sattler and PC candidate Ali Chabar.
The byelections were the first opportunity to see how voters were judging Premier Kathleen Wynne after six months on the job, dogged by scandals inherited from McGuinty's administration, including the costly cancellation of two gas plants.
Wynne had acknowledged that the byelections would be tough for the minority government.
Finance Minister Charles Sousa echoed that sentiment as the results rolled in Thursday night.
"In a byelection, it's always more difficult for a sitting government to retain all those ridings," he said.
"I certainly recognize that the people of Windsor and London have spoken. We're listening, we recognize that it's a byelection, an indication that all governments have to be more attentive to the needs of the communities."
Thousands of voters have spoken and want a change at Queen's Park, said NDP Leader Andrea Horwath.
"We won't take that trust for granted," she said from Windsor, where former TV reporter and city councillor Percy Hatfield sailed to a landslide victory.
Claiming a coveted Toronto seat will be a boost for the Tories after being shut out of the city since 1999. Opposition Leader Tim Hudak acknowledged after a disappointing loss in the 2011 general election that making inroads in Toronto would be key to winning the next time around.
Tory hopes for Etobicoke Lakeshore were pinned to star candidate and deputy Toronto mayor Doug Holyday, who was pitted against fellow city councillor and Liberal Peter Milczyn.
The two opened up neck-in-neck, but Holyday pulled ahead, leaving Milczyn behind as the results poured in.
The tough competition between the two sparked a war of words between the governing Liberals and Toronto Mayor Rob Ford, who campaigned hard for the two Toronto Tory candidates.
Ford didn't mince words earlier this week about what he thought of the scandals, calling the government corrupt and saying voting for the Liberals was akin to handing a gun to a bank thief and telling them to rob another bank.
He also urged voters to support the New Democrats if they didn't vote Conservative.
Transportation Minister Glen Murray fired back the next day, criticizing Ford for injecting himself in the byelection and taking credit for a subway extension to Scarborough that the province was largely paying for.
He labelled Holyday a "mouthpiece candidate who is basically running now on the coattails of the mayor and his brother."
Ford called Murray's comments "unbelievable" and an "embarrassment."
"The provincial government affects us. You have to get involved," he said. "You choose a candidate and you get behind them."
The Liberals were one seat short of a majority before the five resignations, and Wynne will still lead a minority government Friday regardless of the outcomes of the byelections.
Low voter turnouts are believed to help sitting governments, and both opposition parties were fuming when Wynne scheduled the byelections just before a long weekend at the peak of the summer vacation period.
- With files from Keith Leslie.
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