Robert-Falcon Ouellette is seeking the Liberal nomination in Winnipeg-Centre, a seat currently held by New Democrat Pat Martin.
The only other nomination candidate so far, Allan Wise, has announced he is dropping out of the race.
Wise says he thinks the inner-city riding would be well-represented by an indigenous person and he adds more aboriginals should be in Parliament.
Ouellette, who is 38, was something of a Cinderella story in last October's mayoral race.
With no organization, name recognition or party backing, he finished a strong third with 16 per cent of the vote and gained attention for speaking about poverty and race issues.
Wise said he is stepping aside willingly and was not under any pressure to do so.
"I think it's the right thing to do, to make sure that the voice of those who haven't been heard in the past will be heard," he said Tuesday.
"I work in community development in the core area, and some of the things I hear from folks — for example, at the school level even — is 'how is it that the management of the school or the teachers that teach our children are not really reflective of the actual population that lives in the area?'"
No date has been set for the Winnipeg Centre nomination meeting.
Wise, who carried the Liberal banner in the 2011 election, said he is not certain yet whether he will work for the Liberals in the next election.
"For now, I'm just going to take some time off to reflect."