Toronto Liberal candidate Joe Volpe says someone displaying an American-based phone number is targeting his supporters in the Italian community with repeated, harassing telephone calls.

Volpe — an incumbent candidate in the riding of Eglinton-Lawrence, who is seen as vulnerable to a potential Conservative breakthrough in Toronto — says angry residents have called him to complain that they have been contacted four or five times in the past week.

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They report being asked, "Do you plan to vote for Joe Volpe? Would you like a lawn sign?"

The residents say the number display shows an area code based in North Dakota.

The only problem is, Volpe insists it's not his campaign doing the calling.

"I think somebody's going through a lot of trouble to create a climate where our own supporters are getting bothered," Volpe told CBC News at his campaign office. "I think it's a classic vote-suppression technique."

The Conservative Party, and their local candidate Joe Oliver, say they have no idea what Volpe's talking about.

"All calls from our campaign are proudly identified as being on behalf of Joe Oliver and the Conservative Party of Canada," a campaign worker told CBC News in an emailed statement. "All calls made on behalf of the Joe Oliver campaign are made from within Canada. We have no contract with any company in the U.S. to do calling on our behalf."

Number traces to North Dakota

Resident Michael Cosgrove, who says he's an NDP supporter who will more likely vote strategically to support the Liberals, showed his telephone call display records to CBC News.

"I immediately became more suspicious. Why am I getting calls from North Dakota?" said Cosgrove, who added he's been contacted twice in recent days. "So I did a bit of a check online and discovered there were other people getting calls."

An Internet search on the number 701-509-8703 traces it back to Minot, N.D. When called, an automated reply plays the following message: "Thank you for calling back. If you are not interested in receiving calls on our special promotions and would like to be place on our Do Not Call List, please press 1. Please allow up to 72 hours to have your number removed from our preferred marketing list."

But the mystery deepens on the internet, where scores of people have complained about receiving calls from the number — not about election issues, but about credit card and bank scams.

Police in Minot say they are not aware of the number or its origins. Police Lt. Jason Sundbakken told CBC News it could be a "spoof number" used by criminals to obscure the true origins of phone call by projecting a fake Caller ID.

Volpe office claims receiving call

Upping the intrigue are claims by one of Volpe's own campaign staff that the mystery number actually called their campaign headquarters.

Marsha Sands has sworn an affidavit before a lawyer to attest to what happened when she picked up the phone at their campaign headquarters on Monday. She said she was asked if she was going to vote for Volpe.

"I said 'Who is this?' I could hear voices in the background," she told CBC news in an interview.

When she pressed further, the caller said she was doing a survey.

"I said, 'Oh fine. What's the name of your company?'" recalled Sands, "and the girl, a female voice, said to me it was Dynamics Research.

"They didn't say anything and I kept repeating, 'Who is this?' And finally they said they were conservative."

Volpe acknowledges he has no proof who was on that telephone, or who was behind the calls, but he is now consulting lawyers and has called the Elections Canada candidate support line on what to do.

CBC News contacted Dynamics Marketing in Cooperstown, N.D., and they said they had no work contacting Canadians for the election. A spokesperson said they are concerned someone might be using their name, and have contacted local authorities to investigate.

Volpe subject of 2007 call campaign

CBC News has learned Volpe was the subject of a 2007 telephone survey of voters in Eglinton-Lawrence, initiated by the research firm Campaign Research.

The company's co-founder Richard Ciano — who at the time was national vice-president of the Conservative Party of Canada —told CBC that he was hired to do research, but he refused to say who his client was. Ciano's company formed the questions but subcontracted the telephone work to Opinion Search Inc.

"From time to time we ask questions about controversies involving candidates and in that case we asked questions involving a controversy he had been involved in," Ciano said.

Volpe asserts residents called him to alert him surveyors were asking misleading and defamatory questions. One resident claimed callers asked if they were aware Volpe was "charged with taking $5000 donations from twins".

But Volpe was never charged with such a thing. He engaged a senior parliamentary lawyer who issued a "cease and desist" letter. Both Opinion Search Inc and Campaign Research vehemently deny asking such a question or misrepresenting themselves in any way.

"I'm not saying we made any allegations he was convicted or charged or anything like that. We simply would have asked about awareness of the controversy and what people may have thought about it," Ciano told CBC.

Asked about this latest barrage of phone calls in Eglinton-Lawrence, Cianno expressed disgust.

"This sounds super-shady. Someone is breaking Canadian law and the CRTC regulations in terms of what has to be identified (in incoming telemarketing calls}," Ciano explained.

"We would never do that. Absolutely not. Categorically not. First, callers should identify themselves and where they are calling from, and the call has to have a proper CID (Caller Information Display)."

"This raises serious legal and ethical issues," Ciano said.

When contacted by CBC News Elections Canada's media spokesperson Grace Lake indicated she'd never heard of such phone-calling techniques as reported by the Volpe campaign.

The elections agency is now reviewing whether any laws are being broken, and whether the calls — either on behalf of an undisclosed political party or a third-party interest — constitute any infringement on campaign rules in Canada.

Elections Canada's legal department said the calling campaign could potentially contravene sections 331 and 358 of the Elections Act.

The legal department said it has not made any determinations. Though the caller is unknown, the department said that based on what it knows, the scheme could be breaking laws that prohibit foreigners from trying to sway electors during a campaign and ban third-party advertising by non-Canadians.