OTTAWA - The death of Jack Layton was a devastating blow to the NDP at the top of its game and critics questioned the party's prospects without him.

Now a year after Layton's passing, Quebec MP Thomas Mulcair is leading a team of 101 New Democrats in the House of Commons and is ready to hammer Prime Minister Stephen Harper.

"I think it was one of the saddest and most rewarding years all at the same time, all hinged around Jack's passing," said NDP House leader Nathan Cullen, citing the NDP has defied critics and is polling "better than ever."

Brian Topp, a strategic advisor to the late leader who placed second in the NDP leadership bid, said the NDP's future was one of Layton's greatest concerns when he was dying of cancer.

"One of the things that worried Jack in his last days...was (if) the party going to be OK as he couldn't continue. The answer is we are doing just fine," Topp said. "We elected a great new leader, he is doing very well."

But political scientists believe the new leader's approach to fighting Harper is more ferocious than Layton's method.

"Mulcair is more willing to stand up and punch you in the nose," said University of Toronto professor Nelson Wiseman. "It is to his advantage to punch at Harper. Harper isn't perceived as some nice softie."

Mulcair has already made controversial comments about Canada's resource boom hallowing out manufacturing in Ontario and Quebec and its impact on the Canadian dollar - an economic theory he called the "Dutch disease."

"Tom now has the mandate to build on what Jack has been able to establish," said the NDP's former principal secretary Brad Lavigne. "The tough sloughing...that is Jack's legacy. Where Tom's leadership comes in is how we get the job done. We finish the project."

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For the NDP, 'the project' means ousting Harper from government in 2015.

But Topp said the completion of that project needs to be based on more than mud slinging.

"You can be critical of your opponents. Jack Layton was always very critical of his opponents," Topp said.  "This will be a test of our party, there's no doubt about it. Canadians are not just looking for criticisms. They want to know what our alternatives are."

Kristy.Kirkup@sunmedia.ca
Twitter: @kkirkup