A sign of where the real battle will be fought, all three party leaders visited the heavily-populated and fast-growing region, which was a mix of Liberal and NDP seats provincially but where many ridings are held federally by Conservatives.
Premier Kathleen Wynne's campaign bus crawled north through rush hour traffic on Highway 404 to her old high school in Richmond Hill, where she talked to students about the importance of leadership and how to make a valid argument without attacking your opponent.
"At this very school, I learned that if you want to really have everyone come on side, in the end it's about being positive and not tearing each other down," said Wynne.
Progressive Conservative Leader Tim Hudak ventured west to a recording studio in nearby Mississauga, where he talked about his five-point plan to create one million jobs over 10 years.
"What the province needs right now is a premier who is focused like a laser on job creation and a long-term plan to turn our province around, not short-term popularity," said Hudak. "My message here: there is hope. There's going to be opportunity. There's going to be a million new jobs."
NDP Leader Andrea Horwath campaigned in Brampton, including some old-fashioned "mainstreeting," where she attacked her opponents and said the New Democrats would protect the average voter.
"The Liberal government has been plagued with scandal and with waste and basically put a budget together to try to cover up, frankly, their dismal record," said Horwath. "The Conservative party spent a lot of time making noise and causing trouble but not really focusing on the results of Ontarians."
The Conservatives decided to make public Monday their statement of defence in the $2-million libel suit filed against Hudak, the PC Party and energy critic Lisa MacLeod over allegations they made against Wynne regarding the deletion of emails on two gas plants cancelled by the Liberals.
The Tories deny they did anything wrong when they suggested Wynne "oversaw and possibly ordered the criminal destruction of documents" related to the $1.1-billion cancellation of gas plants in Misssissauga and Oakville prior to the 2011 election.
"I'm not going to back down," vowed Hudak. "When people see a billion dollars (added to) their hydro bills, blown to save Liberal seats, there's another reason why we need change."
In the statement of defence, the Tories say they had a "legal, social and/or moral duty" to make the comments that the Liberals claim were defamatory.
Wynne said she wasn't worried about the impact of the libel suit on the election campaign.
"When there are false allegations made, it's very important that I stand up to those and that I make it clear that that's unacceptable," she said.
"So the legal process will carry on, but we're now into a period where it's important to talk about how we're going to make Ontario a better place."
Horwath said the Liberals had a plan to privatize the Toronto Transit Commission, an idea Wynne accused the NDP of fabricating.
"That's a made-up comment because I have never, ever talked about privatizing the TTC," said Wynne. "It's completely made up."
Wynne spent much of the weekend in a verbal sparring match with Prime Minister Stephen Harper on her call to create a mandatory provincial pension plan, which he called a tax that voters would not like, an issue she revived again on Monday.
The maximum pay out under the Canada Pension Plan is about $12,500 a year, which an Ontario Retirement Pension Plan would double to $25,000, said Wynne.
"Stephen Harper when he retires is going to have about 10 times that amount in his pension," she said. "So the reality is that if he doesn’t believe that the Canada Pension Plan should be enhanced, then he should move out of the way and let Ontario do its work."
Wynne also talked to students about how she and her friends fought with administrators at Richmond Hill High School in 1971 so girls would have the right to wear pants to school.
"Then I became the first Ontario premier to wear a skirt to work."
Even though the slow, staggered, not-yet-official start to the campaign slipped into second gear Monday, the legal writ is dated for Wednesday, May 7.
Wynne called the election on Friday after Horwath said the NDP had lost confidence in the minority Liberal government and would vote against the budget, which the Tories had already vowed to try to defeat.
— With files from Maria Babbage and Diana Mehta.
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