The lingering question of who will lead the NDP after the death of Jack Layton was thrust into focus on Monday, as party president Brian Topp became the first candidate to officially announce his bid for the top job.

While Topp is a well-known strategist among New Democrat insiders, Canadians will get their first public glimpses of the leadership hopeful as he begins travelling across the country this week to rally support.

Speaking on CTV's Power Play on Monday afternoon, Topp explained that he aims to push for the leadership while ensuring that the campaign remains civil and respectful to Layton's legacy.

"I was with Jack a couple of days before he passed away, and we talked about a lot of things, but nobody was thinking about replacing Jack," he said.

It's expected that Montreal MP Thomas Mulcair will also enter the race, along with B.C. MP Peter Julian.

Topp (first) made his announcement in Ottawa, alongside Quebec MP Francoise Boivin and former NDP leader Ed Broadbent.

Power Play host Don Martin suggested that Topp has the support of many NDP stalwarts, and that he already has Layton's team behind him.

But Topp, who was wearing what he called a "government-orange" tie, said he plans to be out on the campaign trail for "a long, long time" in order to get more memberships in the party.

"We're all members of Jack's team. The tone in which we conduct this leadership is going to be quite important," he added, noting that Canadians will be watching "unusually closely," as the NDP has a chance to form the next government.

News of Topp's decision comes at a time when the New Democrats are riding high in the polls, despite the many changes on the horizon for the party.

A new Nanos Research poll conducted for CTV and The Globe and Mail found that 33.1 per cent of surveyed voters said they support the New Democrats.

That puts the NDP just behind the Conservatives (39.5 per cent) and well ahead of the Liberals (20.7 per cent), the Greens (3.4 per cent) and the Bloc Quebecois (2.6 per cent). One in five respondents said they were undecided.

Pollster Nik Nanos said the Aug. 29-Sept. 1 survey numbers, considered accurate to within 3.2 percentage points, suggest that the New Democrats have made recent gains in Quebec.

Topp becomes first official leadership candidate

Topp is the first NDP candidate to formally declare his intent to seek the party leadership.

He told reporters Monday that he will be resigning from his position as party president as soon as he files his candidacy papers.

Topp said he also intends to run for a seat in the House of Commons at an "appropriate" opportunity, whether or not he wins the NDP leadership contest.

For now, Hull-Aylmer MP Nycole Turmel is serving as the interim leader of the New Democrats.

Turmel took on the interim leader job in July, when Layton announced he was stepping down from his job to seek medical treatment for cancer.

She is expected to serve as interim leader until the New Democrats pick their next leader at a convention in Toronto slated for March 24.

Whomever the NDP selects as its next leader will immediately become the leader of the Opposition.

This same individual will also be tasked with leading a parliamentary caucus that includes dozens of rookie MPs.

In his endorsement Monday, Broadbent said Topp had the "political and intellectual substance" needed to lead the New Democrats in the years ahead.

Boivin said she is supporting Topp's bid for the NDP leadership and will not be running for the position herself.

But as the NDP's support rises among voters, so do questions about whether or not the party should merge with the Liberals in order to overpower the Conservatives.

"I don't think we have to become Liberals to win," said Topp.

But he was quick to add that one of Layton's lasting legacies was his willingness to work with others, for the common good.

"In a minority Parliament, in which there's a clear majority that we could assemble to put together a government -- I think we should," he said.

Topp's long-term ties to the New Democrats

Topp's ties to the NDP date back more than two decades.

He started off working for Phil Edmonston, a single-term Quebec MP who won a seat in the House of Commons in 1990.

A few years later, Topp took a job working for former Saskatchewan premier Roy Romanow.

Topp has also helped manage federal NDP election campaigns, and was one of the key negotiators in the failed coalition between the Liberals and New Democrats in 2008.

He wrote a book about his experience in the coalition negotiations last year and became the national NDP president in June.

Topp was born in Longueuil, Que., to an anglophone father and francophone mother.

He studied history at McGill University and later started a print shop in Montreal.

When questioned about his lack of experience in the House of Commons, Topp joked that "every once in a while somebody named Brian from Quebec comes in and gives it a try," making an apparent reference to former prime minister Brian Mulroney, who was also born in Quebec.

Broadbent said his decision to support Topp's bid for the NDP leadership was not that different from his decision to support Layton when he sought the same job in 2003. Both men had not won a seat in the House of Commons before becoming NDP leader, and Broadbent believes they both had the kind of leadership skills needed to move the New Democrats forward.

"Now we need another builder, one who will take us from leader of the official Opposition to the Prime Minister's Office," Broadbent said.

With files from The Canadian Press