The Ontario election race might be a whole lot closer than you think.

An investigation released Monday into a polling company's admitted "failure" in Calgary's recent mayoral election is prompting the firm to cast doubt on the method it used.

That same method is being used in the Ontario polls that show the biggest leads for Patrick Brown's Progressive Conservatives over Premier Kathleen Wynne's Liberals.

The polling firm Mainstreet Research says the method it used in Calgary, known as interactive voice response (IVR), underestimated support for Mayor Naheed Nenshi by a wide margin, by failing to survey enough younger voters. These polls, sometimes described as robocall polling, ask voters to indicate their answers by pressing numbers on their phone keypad.

"We missed a lot of these young voters because they are harder to reach," said Mainstreet president Quitto Maggi in a statement following the release of the investigation. The investigation also revealed that younger voters who were reached by the pollsters were significantly less likely than others to respond to the questions. It means the firm's poll results in Calgary likely overestimated older, more conservative voters.

"While IVR is still very much part of the present of polling, it may not be part of its future, said Joseph Angolano, vice president of analytics for Mainstreet Research in his investigation report. "We might be starting to witness the beginning of the end for telephone polling."

All this could have implications for how you view the Ontario election race. Polls that are using different methods are showing different results, CBC polling analyst Eric Grenier revealed last week. .

The polls showing the closest race in Ontario are conducted online. They draw from a large pool of tens of thousands of voters, allowing the pollsters to pick a sample that they say is representative of the population, although it is not randomly selected.

Polls conducted by Campaign Research Inc. using this method suggest Wynne and the Liberals have narrowed the gap with the Progressive Conservatives over the past six months. The firm's most recent poll released on Friday put the Liberals and the PCs in a statistical dead heat.

The polls that show the Liberals trailing by the widest margin have been conducted using IVR, by Mainstreet and Forum Research.

In every Forum Research poll for the past year, the PCs have led the Liberals by at at least 13 points. Forum's most recent poll released earlier this month puts the Liberals in third, 16 percentage points behind the PCs. Mainstreet's last Ontario poll was conducted in May and gave the PCs a 14 point lead over the Liberals.

The stark differences in the poll results raise questions: Are people who are unhappy with Kathleen Wynne somehow more likely to respond to robocall polls? Or are the online panels under-representing conservative voters?

Problem getting young people to answer poll

Campaign Research no longer uses IVR in its political polling because its shortcomings have become too significant, said the firm's president Richard Ciano..

"The problem isn't necessarily finding young people to call," Ciano said Monday in an interview with CBC News. "The problem is actually getting them to complete the survey."

The lack of response from younger voters to IVR has intensified in just the past two years, said Ciano.

"They screen the calls. If they don't recognize [the number] they don't pick up. And even if they do pick up, when they understand that it's a phone survey, they're just not interested."

PC Leader Patrick Brown addresses the Ontario Progressive Conservative Party convention, in Toronto on Saturday, Nov. 25, 2017. (Chris Young/The Canadian Press)

The president of Forum Research, Lorne Bozinoff, points to his firm's accurate predictions of the results of the B.C. and Nova Scotia provincial elections this year, as well as the Calgary mayoral race, as proof that IVR works.

"The most important thing in looking at this is the track record," said Bozinoff in an interview with CBC News on Monday.

Bozinoff rejects any notion that Forum's polls are missing younger voters. His IVR method uses "random digit dialling" to call both cellphones and landlines.

"Every single person in the province has an equal probability of us calling them," said Bozinoff. "As long as you have a cellphone or a landline, you have a chance of being surveyed by the Forum poll."

He also said the response rate to his firm's political polls is high.

"People are really anxious to give their comments," said Bozinoff. "They love doing ... short IVR political surveys."

Bozinoff dismisses polls of online panels as "not scientific," unable to indicate a true margin of error since the sample is not random.

"You can't rely on them," he said. "These are people who want to do surveys all day long, they're not like you and me."