Elections Canada says a printing error is to blame after a Vancouver teacher who tried to vote in the advance poll on Friday got two spoiled ballots with pre-markings on them.

Chris Quarrie went to vote Friday at the West Point Grey United Church, near the University of British Columbia in the Vancouver Quadra riding, but found a black streak on his ballot next to the circle for the Conservative candidate.

"It didn't look like a pen. It looked more like a printing error or something. It looked like half an X essentially, like half of an X, and I gave it back and said, 'Look, this doesn't look right,'" he told CBC News Monday.

Quarrie showed the poll officials, who were concerned and declared the ballot spoiled before giving him another one. But he said the second ballot had the same marking — though this time it was even darker and next to the Green candidate's name.

Quarrie returned the ballot again to what he called an increasingly concerned polling staff, who declared it spoiled and gave him his third ballot — clear and unmarked — on which he finally cast his vote.

John Enright, a spokesman with Elections Canada, said he was aware of an incident in Vancouver that fit this description, but did not know exactly where it happened. In this circumstance, he said, the chief returning officer determined there was a printing issue and that there was "no malfeasance" with the ballots.

"The ballots, when they are on the printing machines, sometimes there's printing errors that slip in. So it's a result of printing the ballots, black on white, and sometimes some ink spills into the white area of the ballot," he said.

Enright said he is not aware of any other instances of dirty ballots in this election.

Ballot error 'extremely rare'

Enright told CBC News the occurrence is "extremely rare." He said that in the 30 years he has worked elections, he has only heard of it once or twice.

"Frankly, it's even more rare for the ballot to end up in an elector's hand, because the poll officials are doing due diligence," he said.

Enright explained that poll workers are trained to count their ballots and look through them for anything suspicious, including markings, before they open up the polling station for the day.

"They are zooming through stuff and they try to catch those when they can," Enright said. "This one got away from them. They missed it."

Spreading the word

Quarrie said he did not start thinking about the severity of the incident until he left the polling station.

"I figure, once, OK, maybe I was just the one guy who gets the ballot with this thing on it. But the fact that I get two in a row, that's what kind of had me worry [that] you know, this may be a common thing," he said.

He posted a public status update on his personal Facebook page late Friday night, telling his story and reminding voters to make sure they get a "clean, unmarked ballot." His post has now been shared more than 19,700 times.

Quarrie is worried the printing problem might be more widespread, which could lead to spoiled ballots.

"Surely, if you gave me two in a row that had the streak, how many people are coming in here not really noticing the [streak], putting their X on their ballot, putting the ballot in the box, and then during counting those ballots get considered spoiled and then tossed out."

"I just wanted everyone to be aware. Like just look at your ballot before you vote, just take a quick look over the circles."

In the 2011 federal election, there were 99,428 "rejected" ballots, making up 0.7 per cent of the more than 14.8 million ballots cast, according to Elections Canada.