Manitoba MP Niki Ashton joined the race to replace Tom Mulcair as leader of the NDP today, promising to fight growing inequality and injustice in Canada.

Describing herself as a proud democratic socialist and eco-feminist, Ashton said years of "neo-Liberal policies" have had a dramatic impact on Canada, leaving more people marginalized as wealthy CEOs reap greater profits.

She vowed to push back against the tide of privatization, deregulation and austerity.

"We must challenge the power of Canada's elites," she said. "The rich and powerful who are benefiting from growing inequality in our country. It's time to call out a system that is rigged to benefit the few at the expense of the many. It's time to take back our country."

Ashton is the fourth person, and first woman, to vie for the leadership. Peter Julian, Charlie Angus and Guy Caron earlier announced their candidacies.

Ashton, 34, launched her bid at an event at 25OneCommunity, a co-working space for progressive organizations and individuals in downtown Ottawa.

Ashton told supporters Canadians are living in a time of unprecedented inequality, and warned the disparity will get worse, especially for young people, unless urgent steps are taken.

"The reality is, just like the U.S., we are losing more good-paying jobs and just like in the U.S., we are becoming more and more unequal," she said.

'Growing a movement'

The campaign launch message echoed that of defeated U.S. Democratic nominee Bernie Sanders, who railed against the growing income gap and corporate elites. Ashton's slogan on her podium read: "Growing a movement, together."

Ashton appears in a segment on This Hour Has 22 Minutes tonight, and said it would be "a dream come true" if Sanders came to Canada to campaign for her.

First elected in the 2008 federal election, Ashton represents the northern Manitoba riding of Churchill-Keewatinook Aski.

She was one of seven candidates in the NDP's 2012 leadership campaign to replace Jack Layton, when Mulcair took the helm.

Ashton said she was proud to be part of the "Jack Layton generation," and said the NDP's disappointing election results in 2015 reflect the fact Canadians were looking for "fundamental change" after 10 years of Stephen Harper's Conservatives.

Jagmeet Singh, deputy leader of the Ontario NDP and an MPP for Brampton, Ont., is also considering a run, as is former Ontario union leader Sid Ryan.

July 3 is the deadline for candidates to get their name on the ballot for the NDP convention and leadership vote in October.