An independent candidate vying to fill Julie Bishop’s old seat has apologised for forwarding fake polling to the West Australian newspaper, which prompted a front-page story suggesting she would win a staggering swing of 20%.

Louise Stewart, standing for Curtin, and her campaign team forwarded polling purportedly from professional pollsters ReachTel that showed she was in contention to take the Perth seat of Curtin from the Liberals.

The results were published by the West Australian on Saturday under the headline “Blue-Ribbon Bloodbath”, saying Stewart was in a 50:50 contest with the Liberal candidate.

The exact origins of the polling are still unclear. It came to Stewart’s office from a group called Independents Inc, which she wrongly believed to be associated with the son of Malcolm Turnbull, Alex Turnbull.

Front Pages Today (@ukpapers) Blue-Ribbon Bloodbath. Exclusive: Liberal vote slump in prized seat of Curtin delivers challenger a sniff of victory - https://t.co/4yggcsGIpY @AnnabelHennessy#frontpagestoday #Australia #TheWestAustralian pic.twitter.com/jfIIs8PLwE

Stewart has intimated that senior WA Liberals may be behind the hoax, though is yet to provide any evidence to substantiate that claim.

On Tuesday, she apologised for her role in the fake polling and ensuing front-page story, saying there was no intention to “mislead” voters. Stewart blamed the error on “inexperience” and said she took “total responsibility”.

“We have had no contact with Alex Turnbull, Alex Turnbull is not funding my campaign, but the email came from Independents Inc, so we thought it was legitimate,” Stewart told Perth radio station 6PR.

“As I said, my campaign team made a mistake … it should never have gone to the West [Australian]. Now we are trying to identify who actually has been responsible for this poll.”

In earlier statements, Stewart has demanded Mathias Cormann, the finance minister and a senior Liberal in WA, explain whether the party was behind the campaign. Cormann has flatly denied the suggestion and rubbished it as a conspiracy theory.

The prime minister, Scott Morrison, entered the fray on Tuesday, saying Stewart’s handling of the polling has shown she should not be elected.

“She has shown a great deal of poor judgment and I think that is what is on display to the electors,” Morrison told reporters. “I believe the electors in Curtin will rightly mark her down on that.”

ReachTel, which no longer publishes polling under that company name, and associated research company UComms have confirmed they had no involvement with the poll.

Stewart said the polling was emailed to her team from a domain name of “independentinc.org.au”.

The domain name is similar to a term Liberals have used to describe Alex Turnbull’s support for various independent campaigns. The group does not exist and Turnbull and Stewart say they have had nothing to do with each other.

Guardian Australia understands that a tracking pixel was then used in an attempt to ascertain who was behind the email address. Tracking pixels are attached to emails, which, when opened, can reveal basic information about the recipient.

The pixel detected an IP address in central Perth.

Stewart used the tracking data to link the fake polling to the Liberal party.

“I’m not making that leap, I’ve been told that on data provided, on data that Alex Turnbull has access to,” she said.

Guardian Australia understands the IP address in no way provides conclusive evidence of Liberal involvement, but does not rule it out, given the Liberals’ headquarters is in the same area.

Stewart has suggested the matter could be taken up by police. She said she is reconsidering where her preferences go as a result of the issue.