Thousands of protesters from more than 90 labour and community groups chanted slogans and waved placards as part of a province-wide campaign to tell Premier Dalton McGuinty and his minority government its budget cannot stand.
The masses that packed the grounds of Queen's Park "are sending a signal to this premier that this budget is grossly unfair," said Sid Ryan, president of the Ontario Federation of Labour.
NDP Leader Andrea Horwath told the cheering crowd she would rather avoid triggering another provincial election but would keep pushing to change what she called a "profoundly flawed" budget.
"We're showing the people of this province that we are prepared to work to make the minority government work, but we're also showing them the sort of Ontario we can build together," she said.
Municipal Affairs and Housing Minister Kathleen Wynne said that while some may be unhappy with parts of the budget, she doesn't think anyone wants an election so soon after the October ballot.
"I think (voters) gave us a pretty clear mandate... to work together," she said.
The demonstration came just three days before the Liberals face a crucial vote that could send them back to the polls.
At least two opposition members must support the budget in order for it to pass, and the Tories have already vowed to oppose it.
The Liberals and the NDP have been haggling over a deal that would keep the province from plunging into an election.
On Friday, McGuinty agreed to deliver on two NDP demands, saying he'll increase support for child care and the Ontario Disability Support Program.
However, the government won't raise taxes to pay for the added assistance, meaning the money will be diverted from existing programs or offset by other cost-cutting measures.
Earlier Saturday, Horwath said she was pleased to see her party's demands gaining ground.
But she wouldn't say whether it will be enough to secure her support in Tuesday's vote.
"I'm not the kind of person that's a 'my way or the highway' person but I am very, very concerned and I think Ontarians agree with me," she said.
McGuinty has prided himself on maintaining good relations with the unions. But he has come down hard on them lately as the government grapples with a massive deficit.
Beth Carey, a Grade 8 teacher from Hamilton, said the Liberals' compromise is encouraging but insufficient.
Years of gains in education remain under threat due to proposed service cuts and wage freezes, she said.
"It seems like right now, (McGuinty) has got his priorities a little mixed up," she said at the rally.
"I want to remind him that kids are important."
Note to readers: This is a corrected version. A previous version mistakenly identified Kathleen Wynne as the minister of education.
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