MONTEBELLO, Que. — Tom Mulcair gained a reputation as a fierce competitor in the House of Commons, but when he appeared in the first televised leaders debate in the last election campaign, he seemed far less confident; even his smile appeared to be strained.

Was the federal NDP leader, largely considered to be the front runner, encouraged to be himself?

Thomas Mulcair is applauded by members of the NDP caucus following his speech during a retreat in Montebello, Que. (Photo: Adrian Wyld/CP)

These questions, as well as other structural reviews, are being discussed as the NDP and its leader attempt to plot a path forward now that the party has been reduced to third party status — down to 44 MPs from 95 when the campaign began.

As he looks back on what happened, Mulcair, 61, seems ready to identify some areas for improvement.

"The preparations for those debates was an excellent example of something that came up short," Mulcair said in a wide-ranging interview with The Canadian Press on Monday at the NDP's caucus retreat in Montebello, Que.

This realization has been challenging on a personal level, he noted.

"It is frustrating because you want to be a good candidate on top of being a good leader. So you listen to the advice of people you respect and sometimes the result is not there," Mulcair said.

"But no matter what, the person making that decision is me. I have to learn, the party has to learn, the structures have to be refined."

"I have to learn, the party has to learn, the structures have to be refined."

Mulcair, who is resolved to stay at the helm of the New Democrats, has spent the past three months in meetings across the country to look at what worked and what didn't during the punishing election campaign — the longest in modern Canadian history.

His political future will be put to the test in Edmonton in April, where he will need more than 50 per cent support from delegates at the party's convention to carry on in his role.

Mulcair said he plans to stay on as long as he is convinced the NDP can form a government and put its ideas into action.

But while he seems ready to confront some painful lessons from the campaign, he is far from apologetic about the party's core messages.

"Despite the ups and downs of that campaign, despite the sometimes unvarnished truth that came out about very specific aspects of the campaign ... I think that there's nothing structural in our offer, there's nothing about our ability to move this forward that will stop us from forming the government in the future," he said.

NDP taken more seriously in 2015

The NDP's vision was taken more seriously in 2015 than at any other point in the party's history, Mulcair added.

Mulcair said he understands there is a "grace period" after a new government comes into power but he is planning to push for accountability from the Liberals on issues including the economy, the environment and electoral reform.

Nathan Cullen, a B.C. NDP MP who ran against Mulcair during the 2012 leadership bid following the death of former leader Jack Layton, said he has full confidence in his party's frontman.

"We need an articulate voice in Quebec and outside of Quebec," Cullen said after the leader delivered an address to caucus Monday morning.

"We need somebody who is able to take on a government — forcefully with intelligence. We need somebody who has their convictions. I just watched that guy give a speech."