An earlier version of this story has been updated to reflect issues with the data flagged Saturday by the pollsters at Converso Research.

The pollster behind a survey suggesting Manitoba's Progressive Conservatives and New Democrats are in a "dead heat" now says there's a weighting issue with his data.

On Friday, Toronto consulting firm Converso Research issued a poll suggesting the previous gulf in popular support separating Manitoba's New Democrats and Progressive Conservatives had narrowed to the point where the two parties are now statistically tied with only weeks left before voters cast their ballots.

The uncommissioned interactive voice response (IVR) poll was the first public opinion research survey conducted by Converso Research. It surveyed 1,127 Manitobans between July 28 and Aug. 7 and found 30 per cent of respondents said they would vote NDP and 31 per cent PC heading into the fall election.

Another 11 per cent said they intend to vote Liberal; six per cent claimed they'll go with the Green Party; and another six per cent chose not to say. Fifteen per cent remain undecided and one per cent said they would vote for another party altogether.

"Despite leading in polls since their election in 2016, Brian Pallister's Progressive Conservatives have fallen into a dead heat with Wab Kinew's NDP right at the beginning of the 2019 provincial election," reads the report out Friday from polling firm Converso.

On Saturday evening, Converso managing director Carl Mavromichalis said the firm has discovered a weighting issue with the data and is reviewing the poll.

"There is an issue with the weighting of our poll. We are working to correct the issue as quickly as we can and will reissue the results and a full report," Mavromichalis said via email.

"It is unclear whether the weighting issue will impact the results," he said.

"Having said that, we will be taking the time necessary to correct any issues that we uncover. I'm hopeful that we can provide an update within 48 hours. We regret any issues this may have caused."

Earlier Saturday, veteran Manitoba political scientist Chris Adams expressed surprise with the results, as all recent polls suggested the Progressive Conservatives are leading the Manitoba pack by a large margin.

"It doesn't mean that they're wrong, but I was surprised to see the NDP is tied with the Progressive Conservatives," said Adams, adjunct professor in political studies at the University of Manitoba.

"All the polling data we've looked at, that I've looked at over the past four years, has something different, but at the same time it's an election campaign and numbers can shift."

The results contrast two Probe Research polls, including one in March that put the PCs 12 points ahead at 42 per cent support provincewide.

A more recent poll in June suggested the gulf was widening, not narrowing, between the NDP and PCs; the New Democrats slid to 26 per cent while the Tories held on at 42 per cent in that sampling.

ICYMI: Tories continue to hold commanding lead as early election campaign gets underway <a href="https://t.co/0OjRODfqNZ">https://t.co/0OjRODfqNZ</a> <a href="https://twitter.com/hashtag/mbpoli?src=hash&ref_src=twsrc%5Etfw">#mbpoli</a> <a href="https://t.co/53JsSgxEco">pic.twitter.com/53JsSgxEco</a> —@proberesearch

Adams said this is the first time he's heard of Converso. He said it's no longer uncommon to see uncommissioned polls, in part, because IVR polling can be done credibly and reliably somewhat cheaply these days.

IVR polling typically employs a recorded voice in place of live interviewers. Callers respond to questions by either pressing phone keys or by responding with voice answers that are recorded for later analysis.

Adams said it's hard to fully assess the quality of the data without knowing the demographic and geographic breakdowns of the sample of about 1,200, which weren't made available in the first iteration of the polling information released to media.

"This is not a polling company, this is not a company that specializes in survey research, so I have to ask where is the sample coming from?" he asked.

A fuller report is expected to be released Monday, Converso said.

The next Manitoba election wasn't slated to occur until October 2020, but Pallister flouted the fixed election date in June by calling for a Sept. 10, 2019, election.

The Converso poll suggests voting preferences by gender skew only one or two points above or below the combined totals for any one party.

By age, the NDP has experienced a bump in the 35-49 bracket — 43.7 per cent compared to the PC's 23.8 per cent. But the two parties are basically tied in the 18-34 demographic — 29 per cent NDP compared to 30.6 per cent PC.

"This is one of the fronts we think the election is going to be fought on," said Carl Mavromichalis, managing director of Converso.

Meanwhile the PCs enjoy a lead among voters between the ages of 50 and 64 — 35.3 per cent compared to the NDP's 24.2 per cent — and 65 and older — 36.8 PC compared to 19.9 per cent NDP.

The PCs also outperformed other parties in terms of living up to the expectations of those Manitobans who voted them into power in 2016. According to the poll, over 25 per cent of PC voters said the Pallister government has lived up to expectations, compared to between 10 and 15 per cent for NDP, Liberal and Green voters.

Noel Copping, communications director for Converso, said the timing of the campaign in the middle of summer doesn't seem to have hurt the level of interest among voters.

"What we have seen is very high scores of motivation to vote, regardless of the party that the people are going to support," said Copping.

"Decided voters seem to be very keen to vote in this election — they seem to be interested and engaged and quite likely to turn out based on our findings."

The PCs captured 53 per cent of the popular vote in the last provincial election, compared to just 26 per cent for the NDP.

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