Mulcair is holding six rallies in the eight days of the tour, which began Monday. It includes interviews with local media, news conferences and photo-ops, including one where he fed a calf at a dairy farm in Brunner, Ont.
The NDP leader is travelling through key ridings in Scarborough and other parts of Toronto, Mississauga, Hamilton and Cambridge, to name a few places, in the hopes of both getting more name recognition and honing both his skills and his message.
Polls have suggested it's a close three-way race between the Conservatives, Liberals and NDP, and Canada's most populous province offers political parties plenty of seats to fight over.
"Ontario is an incredibly important battleground in the next campaign," Mulcair said this week at a news conference at Woodlogix Interiors, a millwork company in Mississauga.
'He's angry. He's strong.'
He was joined by two Mississauga NDP candidates, Fayaz Karim (Mississauga-Streetsville) and Farheen Khan (Mississauga Centre).
When Mulcair asked Khan what she was hearing in the riding she said: "They are telling me: 'I like Tom. He's angry. He's strong."
CBC reporter Catherine Cullen asked Mulcair how he measures his momentum.
"I have different ways of measuring that," he said. "There is the shopping centre test, there is the sidewalk test, there is the airport test — which is very interesting because it has a lot to do with meeting people very quickly. The two thumbs up. The 'you go get 'em, you get it done,' that's the one that we've been getting a lot."
In Cambridge, Ont., which is currently represented by a Conservative MP, CBC News saw "the sidewalk test" in action.
Mulcair was approached on his way to lunch by Wes Mazur, a man who wanted to shake his hand. Mazur, an occupational health and safety consultant, later told CBC News he was "pleasantly surprised to see a bit of orange stripe in a predominantly Conservative and red (Liberal) riding."
Mazur said he hasn't been very into politics but that he liked what the NDP has been doing lately. Accountability and transparency were two of his sticking points with the current government and he said he may just vote NDP for the first time in his life.
Another voter liked the man — but not the politics.
"I think he is a great leader but he works for the wrong party," said Jeff Mizener. "I like him as a person but I don't like the stance the NDP takes on a lot of things."
Another person on the sidewalk said she didn't even know who he was. "He's in government but I don't know his name."
At a rally in Hamilton on Tuesday night, Mulcair pulled in more than 300 supporters to hear his speech.
The NDP leader touched on many of the topics he's repeated on this tour: a promise of one million child care places, a $15 federal minimum wage and keeping the retirement age at 65. The slogan on his posters reads "Ready for Change" and his newly released autobiography, Strength of Conviction, was up for sale at the back of the room – though there weren't many takers.
Hamilton was also the site of a gaffe from the leader, who told CBC News in an interview that Alex Johnstone, the NDP candidate for Hamilton West-Ancaster, was a "wonderful man." Johnstone, a two-time NDP candidate, is a woman.
Mulcair won't be the only politician making a major push in Ontario.
More MPs will be elected in the upcoming election, as the number of seats in the House of Commons has been bumped up from 308 to 338. Of those new seats, 15 are in Ontario, mostly in the densely populated Greater Toronto Area.
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