"Our campaign is already starting," he said in French during a stump-style speech on Sunday to party faithful.
To underscore that point, the NDP announced it has put in place the team that is going to lead it into the next federal election. MPs Jean Crowder and Alexandre Boulerice are to be the architects of the NDP's 2015 election strategy, while veteran strategist Anne McGrath is the party's new national director.
But it was Mulcair's address to the NDP's federal council — and notably his broadside against Liberal Leader Justin Trudeau — that really drove home the point that the campaign is in full swing.
In the speech, he reiterated party pledges on post-secondary education and the eligibility age for old age security. He also took shots at both Prime Minister Stephen Harper and Trudeau.
Trudeau, in particular, bore the brunt of Mulcair's attack. The Liberals under Trudeau have been trying to court middle-class voters in the run-up to the next election, scheduled for Oct 19, 2015. But the NDP leader said Trudeau's upper-class upbringing puts him out of touch with middle-class Canadians.
"The problem is, Justin Trudeau will never know what middle-class means," Mulcair said.
"He just doesn't understand the real challenges that families are facing. Never has. Never will."
There was a time when Mulcair outright refused to utter Trudeau's name. That he is now putting so much emphasis on the Liberal leader may signal that Mulcair sees Trudeau as a bona fide threat to the NDP going into the next election.
Much of the NDP's success in 2015 will rest on how it fares in Quebec, and if it can build on a 2011 performance that saw it win 58 seats of the province's 75 seats, propelling it to official Opposition status for the first time in its history.
On Quebec, too, Mulcair sought to draw a line between himself and Trudeau. The NDP leader pointed out that he, unlike Trudeau, is the only federal leader eligible to cast a ballot in Monday's Quebec election.
Mulcair says the Liberal leader cannot vote because he no longer lives in Quebec, despite representing a Montreal riding.
"You'd have to be a resident in Quebec to be able to vote. I'm allowed to vote," Mulcair said.
"(Being a Quebec resident) gives me the ability to talk about it concretely and have meaning to it."
The NDP leader says he voted in an advance poll for Geoffrey Kelley of the province's Liberal party, who Mulcair says is a long-time friend who he considers a social democrat with deep NDP roots.
Mulcair says his primary home is in Quebec and not at Stornoway, the official residence of the leader of the Opposition in Ottawa's tony Rockcliffe neighbourhood.
Trudeau moved his family to the same neighbourhood after becoming Liberal leader.
"Mr. Trudeau lives in Ottawa in order to be closer to his family," Trudeau spokeswoman Kate Purchase wrote in an email.
"Contrary to the two other leaders, he does not have a paid residence in Ottawa."
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