Wynne told reporters in Toronto on Sunday that although there is a "stark difference" of opinions over the plan — a centrepiece of her campaign — she wants the focus to be on the retirement needs of Ontarians who lack pension support at work.
"The discussion has become about the politics of this. For me, it's about making sure that people who are concerned about their retirement have some security," she said.
"My value system is that we have a responsibility as government to put in place a structure that allows people to have a secure retirement," Wynne added, saying two-thirds of workers lack job pensions.
However, while discussing what she calls the lacklustre support from the Canada Pension Plan, Wynne did take a slight jab at Harper, saying his pension as prime minister has "almost 10 times" the maximum CPP payout.
The apparent rhetorical cool-down came after Wynne said Saturday that if Harper doesn't want to co-operate on her idea for a made-in-Ontario plan then he should "move out of the way" and not interfere with it.
Those comments were in response to the prime minister's criticizing the proposal a day earlier as a tax that would be rejected by voters.
The Prime Minister's Office was also trying to lower the temperature, with a spokesman saying Saturday that the election is for Ontario voters to decide and the federal Conservatives will work with whatever government is elected.
Wynne called a June 12 election on Friday after the NDP said it could no longer prop up Wynne's minority Liberal government, which it said is beset by scandal.
Though the election drive doesn't formally start until Wednesday, Wynne, Progressive Conservative Leader Tim Hudak and NDP Leader Andrea Horwath were all in campaign mode in the Toronto-area on Sunday.
Hudak poured cold water on Wynne talking up her pension pitch and big-spending budget as geared to the needs of working Ontarians, saying only his party can deliver on pocketbook issues.
"She's turned her back on workers in the province. I'm telling workers in Ontario, there's a better Ontario coming. Better jobs. Better take-home pay," he said, touting the Tories' plan to boost employment.
After sailing through a nomination meeting Saturday in Hamilton in which she said Wynne's government wasn't "grounded in the real world," Horwath was to campaign Sunday night in Toronto.
The race began when Wynne decided not to let her government face weeks of criticism before a budget confidence vote it would lose, and on Friday asked Lt.-Gov. David Onley to dissolve the legislature.
Wynne has said she wanted to see her budget passed, and is laying responsibility for the election at the feet of the opposition parties.
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