See how your neighbours voted in our map of 2011 federal election results for Winnipeg by polling division. Click on a polling division to see which riding it was in for the 2011 election and which candidate placed first there.
The black outline reflects riding boundaries for the 2015 federal election.
Small boundary changes could lead to significant electoral consequences in some Winnipeg federal ridings that were close races in the 2011 election, poll by poll election results show.
The consequences of boundary changes are seen most acutely in Winnipeg North. There, incumbent Liberal MP Kevin Lamoureux's support was based in the western part of the riding while the eastern part was firmly NDP.
Lamoureux would likely have lost in 2011 if the updated boundaries in Winnipeg North were in place then. Lamoureux narrowly defeated the NDP's Rebecca Blaikie.
The updated Winnipeg North boundaries now include six polling divisions that were formerly part of Kildonan-St. Paul. Five of the six new polls voted largely Conservative and one voted NDP. If these votes were added to the 2011 election outcome in Winnipeg North, the results would have tipped in Blaikie's favour. The new polling divisions are from the Amber Trails area, north of Leila Avenue.
In the 2011 election, Lamoureux received 9,097 votes and Blaikie got 9,053, giving the riding to Lamoureux by only 44 votes. According to Elections Canada data, if the new boundaries were applied to the 2011 election in Winnipeg North, Lamoureux would have got 9,331 votes and Blaikie 9,440, giving the riding to Blaikie by 109 votes.
MAP: The highlighted polling divisions were part of Kildonan-St. Paul in 2011 and will be a part of Winnipeg North in the 2015 election. Areas in blue indicate polls where the Conservatives placed first, orange for NDP.
The process of deciding federal electoral boundaries, however, is not supposed to take into account previous election results, even though it can change a candidate's ground campaign.
Riding boundaries are reviewed every 10 years to make sure they reflect population growth and the movement of people.
The boundaries were reviewed most recently in 2013, when several tweaks were made to Manitoba ridings.
A three-person commission, holding public sessions and accepting submissions, studied boundaries and suggested changes to maintain the demographic character of ridings, while balancing that with the need to keep the population of ridings relatively similar.
"As much as possible, we try to achieve constituencies with the same population, so everyone's vote is worth the same," said Paul Thomas, professor emeritus at the University of Manitoba and a member of the 2013 Federal Electoral Boundaries Commission for Manitoba.
Many MPs made submissions to the commission with recommendations for new boundaries.
Thomas said Conservative Elmwood-Transcona MP Lawrence Toet made a submission asking for parts of Elmwood to be added to Winnipeg Centre, which is demographically similar to Elmwood and is currently held by NDP MP Pat Martin.
Elmwood is the base for NDP support in Elmwood-Transcona, and based on 2011 election results, breaking off parts of Elmwood would increase the Conservative share of the total vote in the riding. This would be significant for Toet, given he won by a razor-thin margin of 300 votes in 2011.
He is campaigning against the NDP's Daniel Blaikie in this election. Blaikie is the son of the former longtime MP for the area Bill Blaikie.
MPs don't overtly suggest electoral considerations in their submissions.
"They will present views that aren't crassly partisan," Thomas said.
Previous election results are not supposed to be a factor in their decisions in order to avoid U.S.-style gerrymandering in which constituencies are modified to skew the vote in a particular candidate's favour.
Thomas said the commission is non-partisan, appointed directly by the House of Commons and headed by a provincial judge.
"There are political calculations that we aren't supposed to be influenced by, but we do have to take heed of it," he said.
"It's often not convenient for them to see the boundaries change. A candidate makes connections in the community, builds support," Thomas said.
Updated on Tuesday, September 22, 2015 at 8:03 AM CDT: Adds graphic