TORONTO - In many ways, the dust has yet to settle on last May's federal election that gave Conservatives their first majority government in a generation and New Democrats their first-ever crack at official Opposition.

The NDP hit the reset button this weekend, finally replacing the late Jack Layton with a permanent party leader who will provide shading and definition to Canada's 42nd parliament.

Thomas Mulcair steps into the gaping breach left when Layton succumbed to cancer less than four months after his party's electoral breakthrough.

Mulcair, a former Quebec Liberal cabinet minister, arrives just in time for the Conservatives to deliver Thursday's federal budget, their first as a majority and one expected to deliver sweeping changes.

And the new NDP leader paid his foes a singular compliment by suggesting the Conservatives' rigour needs to be emulated.

"Right now we're facing a government that's very tough, very well structured, and we've got to do the same thing," Mulcair told reporters in Toronto on Sunday in his first news conference as NDP leader. "We've got to structure an official Opposition that will bring the fight to them like they've never seen before."

Expect even more pugilistic metaphors than usual in the political press as the country comes to grips with its new parliamentary sparring partner.

After seven months with the inoffensive caretaker Nycole Turmel leading the Opposition in the Commons, Mulcair brings a far more forceful — Tories say "vicious" — persona to the canvas.

And for a Stephen Harper government that has a well-earned reputation for partisan thuggery, the end of this season of shadow boxing seems a welcome thing.

Literally the minute Mulcair was crowned Saturday night at the Metro Toronto Convention Centre, the party carpet-bombed reporters with a scathing email missive calling him an "opportunist" of "blind ambition."

Many hours later, the Prime Minister's Office issued a perfunctory welcome from Harper, but the tone was already set.

James Moore, the Conservative heritage minister, used his observer's perch on the NDP convention floor to describe the new party leader as "a hard-left socialist, a bare-knuckle fighter who's a very aggressive guy."

"They've chosen a fighter and we're more than ready for a fight," said Moore.

Liberal MP Scott Brison, his party's finance critic, was also quick to highlight Mulcair's fiery reputation, noting the contrast with "le bon Jack" Layton and indeed the Liberal's own garrulous interim leader Bob Rae.

"The question is: Do Canadians want to go from a right-wing nasty warrior to a left-wing nasty warrior? Is that what they want?" said Brison.

"Is the best way to combat Stephen Harper to be as nasty and prickly as he is? ... That remains to be seen."

The battling metaphors may well be overplayed.

Certainly Mulcair was already working Sunday to lower the temperature.

Asked about the Conservatives' venomous opening salvo, Mulcair was casually dismissive.

"I think that at some point the secondary school behaviour and that type of thing, a lot of Canadians get tired of it," he said.

"If they can't debate on the issues and they have to go personal, we'll let them continue at that. We've got a different approach."

But rhetoric isn't governing, nor even opposing, and the real tenor of the coming parliamentary season will be set by policy differences — and perhaps an ongoing investigation into electoral fraud being conducted by Elections Canada.

As the Liberal Brison put it: "There's a target-rich environment. I expect we're going to have an exciting session ahead of us."

Moore noted that the government welcomes having a permanent Opposition leader across the floor who will be accountable for his party's positions.

"Now that you have the leader of the official Opposition, the presumptive alternative government, sitting there, what they say matters and it's going to have consequence," said Moore.

"If they want to be treated like a grown-up political party, if they want to be treated as not just some protest movement waving placards and chanting, full of platitudes and chants, then they're going to start being held accountable."

On issues from taxation to trade, immigration and resource and environmental policy, look for clearer lines to be drawn following this week's federal budget.

Mulcair, in addition to attempting to cool the fighter imagery, also downplayed expectations for an immediate parliamentary impact as he realigns the NDP's front bench and critic roles — a job he suggested will take several months.

"When we come back in the fall, that's when the real battle begins," said Mulcair.

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PHOTOS: THOMAS MULCAIR

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• Thomas Mulcair

  NDP Leader Thomas Mulcair comments on the federal budget in the Foyer of the House of Commons on Parliament Hill in Ottawa Thursday March 29, 2012. If there was any doubt that Thomas Mulcair's political universe revolves around Quebec, it was dispelled by his response to Thursday's federal budget. (THE CANADIAN PRESS/Adrian Wyld)

• Thomas Mulcair

  NDP Leader Thomas Mulcair addresses the Economic Club of Canada in Ottawa, Thursday April 5, 2012. (THE CANADIAN PRESS/Fred Chartrand)

PHOTOS: BEST SHOTS FROM THE CONVENTION

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