Federal party leaders were not alone in trading barbs in the first three days of what will be the longest federal election campaign in modern history.
Ontario Premier Kathleen Wynne, who has said she will campaign hard for Liberal Leader Justin Trudeau, was critical on Monday of Stephen Harper's decision to call an 11-week campaign on Sunday.
Today, it was Harper's turn to take a shot at the Ontario premier during a campaign stop in Toronto.
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Harper suggested it was Wynne's poor performance as premier that was to blame for their frosty relationship, after he was asked whether it was politically risky to be picking a fight with the leader of Canada's largest province. Vote-rich Ontario helped propel the Conservatives to majority victory in 2011.
"I think I will observe what a senior official told me when I took office. They said, 'You will have your best relations with the premiers who are doing a good job in their own jurisdiction,'" Harper said, drawing laughs and applause from the crowd.
Harper, who has been criticized by some of Canada's premiers for not meeting with them as a group, defended himself by saying he had had "literally hundreds of meetings and telephone calls" with premiers since his party was elected to office in 2006.
While disagreements between Ontario and the federal government have always existed, the latest irritant between the two leaders stems from Harper's decision not to help Wynne administer Ontario's new pension plan.
"There are Liberal and NDP governments whose major ask of the federal government is that we hike taxes on workers and small businesses for the Canada Pension Plan.
"Workers and small businesses in Ontario and across this country reject that policy," Harper said. "They do not want that, they want options like the tax-free savings accounts that we created and doubled, like the registered pooled pension plan and other benefits.
"Canadians want to make their own decisions on savings, they do not want to be taxed by governments in this country," Harper said.
Harper 'actively obstructs': Wynne
Wynne hit back in a terse statement issued by her office Tuesday afternoon.
"Ontario needs a new federal government to work with. Stephen Harper and his ministers preferred to play political games rather than work with provinces in the best interest of the people of this country. This is particularly the case in Ontario. You only have to look to the example of what has transpired with the Ontario Retirement Pension Plan."
Wynne blamed Harper for adding to the "high anxiety" felt by voters in Ontario over retirement security.
"It is an affront to the people of Ontario and their futures when he actively obstructs what everyone knows is needed," Wynne said, adding that what Ontario needs is "a real partner in Ottawa."
Whether Harper's Conservatives pay a price for picking a fight with the Ontario leader will not be known until Oct. 19.
The latest numbers by analyst Éric Grenier put Harper's Conservatives ahead in Ontario.
"The Conservatives appear to have recently experienced an uptick in support, averaging 36 per cent," Grenier said in an analysis published by CBC on Tuesday.
"That is a gain of four points since mid-July. The NDP has surpassed the Liberals in the average, though at 30 per cent to 29 per cent the race remains tight."