Mulcair spoke to a packed room of supporters in this Toronto suburb about the contributions Layton made to the party and how they would continue his legacy into the 2015 federal election campaign.
"I think that one of the things that Jack brought was his determination and his belief that we could accomplish great things," Mulcair said, adding that the two worked closely together to break through in Quebec.
"I took up the challenge, I worked with him for five years and we believed in what we were doing and the result is there now."
Mulcair also said he shared Layton's "sunny optimism" and "driven determination."
"We're going to make sure that across Canada people understand that the NDP is ready to form a government, stand up to Stephen Harper to make sure that we fight for the things that we hold dearly," he said.
"For example medical care for our families, opening up immigration instead of shutting it down the way the Conservatives have been doing."
Mulcair added that family reunification had become increasingly difficult among immigrants and temporary workers had been brought in without full rights, two things that he wanted to see change.
A cycling event was organized around the community in honour of Layton and Chow, Layton's widow, led an entourage of cyclists dressed in black with a bouquet of flowers on the back of her bicycle.
"We're riding for Jack and to say get involved, get engaged, become active both physically but also socially and politically, make a difference and together we are Jack Layton's legacy," she said.
"New Democrats are united and strong and we're moving forward. We are creating an alternative to say to Stephen Harper that we need a country that has more jobs, better health-care and a life that is more affordable."
Mulcair encouraged support from young people across the country and said that "the NDP is the party for youth."
"Young people are involved. Look at the age of the NDP MPs coming out of the province of Quebec, it's a wave of people saying we can do things differently," he said.
Chow highlighted the fact that in Layton's final letter to Canadians just before his death, he said that young people were a great source of inspiration to him.
"As my time in political life draws to a close I want to share with you my belief in your power to change this country and this world," Layton wrote.
"You need to be at the heart of our economy, our political life, and our plans for the present and the future."
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