It appears the result in one Calgary ward in October's election was a lot closer than previously thought.

Although it doesn't change the outcome of the election in Ward 4, CBC News has learned that almost 500 votes for one candidate were accidentally given to another candidate.

No one knows how the mix-up happened.

Sean Chu defeated incumbent Gael MacLeod by 647 votes, but her team thought the race was much closer — and apparently it was.

Ward 4 official totals

                 Candidate                Total votes Percentage
Sean Chu 9,017 43%
Michael David Hartford 1,138 5%
Blair Houston 2,440 12%
Gael MacLeod 8,370 40%
Yuri Shterngartz 158 1%

At the poll in question, Voting Station 408, winner Sean Chu was marked with 450 votes, MacLeod was marked down as having 30 votes and Michael David Hartford was marked down as having 529 votes — an anomaly considering his results elsewhere in the ward. This one poll accounts for 46 per cent of Hartford`s total votes.

Ward 4 has 17 main voting stations. 

Voting Station 408 official totals 

                   Candidate                Total votes Percentage
Sean Chu 450 39.9%
Michael David Hartford 529 46.9%
Blair Houston 103 9.1%
Gael MacLeod 30 2.6%
Yuri Shterngartz 5 0.4%

In every other poll, MacLeod pulled in hundreds of votes, finishing first or second in each case.

Gael MacLeod

Official election results, by polling station, for Gael MecLeod. The 2013 Ward 4 candidate had sat on city council before the election was called. (Courtesy of Paul Fairie/University of Calgary)

Representatives from MacLeod and Naheed Nenshi’s campaign, were there when the ballots were counted and they say the official results are wrong.

Both remember MacLeod having hundreds of votes — not the 30 that were recorded for her at Voting Station 408

Poll-by-poll results come out 

Though the official results came out late the week of the election, the poll-by-poll results weren’t made public until early November. That’s when the scrutineers — representatives from candidate’s campaigns that observe election workers doing the count — realized there had been an error.

After the discrepancy was discovered, MacLeod raised the issue with the city’s returning officer Barbara Clifford.

At this point the results were final. Clifford said she had the option of applying for a judicial recount — where a judge would oversee the count of all the ballots in court.

MacLeod says she wasn't interested in contesting the result in court as fixing the mistake wouldn't change the outcome — that Sean Chu won.

Going forward 

Though, MacLeod says it does raise questions about how the mix-up happened and what can be done to prevent it in future elections.

“One of the things that we could do as a result of this and council could initiate this is to review the process to see in fact how it could happen. I don't know.”

MacLeod says Calgarians need to be confident election results are accurate.

“It never occurred to me, ever, that there could be anything wrong with the election process or that those counts would be wrong,” she said.

“That just never crossed my mind.”

Political scientist Duane Bratt says the mix-up is a threat to the electoral process.

“I think that is worrisome but I’m not sure that there's any regulation or double-checks or checks and balances that you could do to solve these sorts of problem."

The appeal period expired earlier this month and the ballots were destroyed.