CALGARY -- In a city long considered a Conservative fortress and a province newly enamoured with Premier Rachel Notley's NDP, Justin Trudeau found himself in enemy territory Monday, fighting a political battle on two fronts.

A re-elected Conservative government would just keep breaking Alberta's heart and mire the country in a recession, the Liberal leader said. And the change being promised by Tom Mulcair's New Democrats would be just as fleeting.

Greeted by about 400 cheering supporters in the new riding of Calgary Confederation, a relaxed and confident-looking Trudeau attacked Harper's financial record and his plan to stick to the status quo.

"He's asking Canadians to stay the course," Trudeau said of Harper. "Well, the course we're on has led straight back into recession. When the plan isn't working, the real risk is sticking with the status quo."

Of course, Alberta's no longer the one-horse province it once was -- not since Notley bowled over the old-boys network this past spring and shattered the half-century Progressive Conservative dynasty.

Which means any Liberal leader worth his salt needs to fire his guns in two directions at once.

"Mr. Mulcair? Mr. Mulcair has no answer," Trudeau said.

"He says he wants to help people who work for the minimum wage but his plan to raise the minimum wage doesn't apply to 99 per cent of the Canadians who earn the minimum wage.

"The NDP won't tell you that. They'll say they'll help, but they won't -- and worse, they know they won't. Quite frankly, we've had enough of that type of politics from Stephen Harper for the past 10 years."

Trudeau's Calgary appearance followed Harper's foray into the riding of Mount Royal, long a bastion of Liberal support in Quebec that was once represented by Justin Trudeau's father Pierre.

"You know I'm very proud to be here today -- but I'll promise you, particularly since my riding is in Montreal, I will spend a good, fair bit of time in Montreal as well," Trudeau said.

"I think what it shows is the entire country matters, that we cannot pick and choose the part of the country we want to reach out to."

Harper, too, seemed to have Alberta on his mind Monday. Deficits and big tax increases don't create jobs, he warned.

"We have an experiment on this in Alberta right now," Harper said.

"The Alberta government, the new NDP government, in their first action they are incapable of presenting a budget. They raised taxes... the result is a disaster. It's a disaster and (it's) rejected by the population."

Trudeau seized on that remark as evidence of a bull-in-a-china-shop approach to diplomacy that seems to be Harper's hallmark.

"One of the things that has become clear is that Mr. Harper compromises Canadian interests when he cannot get along or work alongside anyone who doesn't share his ideologies," he said.

"Whether it's the new premier of Alberta, whether it's the premier of Ontario, whether it's the president of the United States he is not putting Canada ahead of his ideology and it reinforces how out of touch he is."

The Liberals haven't elected an MP in Calgary since 1968, but Trudeau said he likes a challenge.

"We have 35 seats in the House of Commons right now," he acknowledged. "We're going to have uphill battles right across the country."

With files from Andy Blatchford in Laval, Que.