The man at the helm of Prime Minister Stephen Harper's last election campaign insists the Conservatives didn't engage in any "dirty tricks" to net their recent victory.

In an interview with CTV's Question Period, Guy Giorno broke his silence over claims that the Tories were behind a string of automated calls apparently aimed at suppressing voter turnout in the last federal election.

"When you're running a good campaign, you don't have time for any shenanigans," the former chief of staff said Sunday.

The interview marks the first time a key Conservative campaign figure has agreed to publically counter allegations that the party is behind a series of "robocalls" which incorrectly told voters in Guelph, Ont. that their polling stations had been changed.

"We took great pains and invested a lot of effort at running a clean and ethical campaign that complied with all laws," said Giorno, later adding that all levels of the Conservative Party are concerned about the calls.

Elections Canada confirmed Friday that it's investigating more than 31,000 contacts from voters across the country who felt they received misleading calls in the last federal election. The unprecedented number of complaints comes after MPs and political parties called on the public to submit any information related to the so-called robocalls.

Opposition leaders have tried to pin the scandal on the Tories, pointing out that a "burner" telephone linked to the Guelph calls was also used to place calls to Racknine Inc., an Edmonton-based call centre company used by the Conservative Party in the past. Court documents confirm that Racknine is not under investigation by Elections Canada.

For his part, Giorno said he has never authorized a campaign staffer to make telephone calls pretending to be from Elections Canada, adding that any calls from the Tories were made under the party's official name.

"Why would the Conservatives call people as Conservatives, say ‘we're calling from the Conservative party' and then mislead them?"

That answer doesn't satisfy NDP MP Joe Comartin who has accused Giorno of parroting the same talking points Harper has used to address the robocalls allegations.

"What wasn't there and what needs to be there is: What has the Conservative Party done about ascertaining what in fact happened?"

Tory MP Dean Del Mastro has said that the Conservative Party has "looked into all its practices" as the robocalls scandal continues to unfold.

"Suppression… a despicable, reprehensible practice"

Balking at the idea that a lower-level staff member may be behind the calls, Giorno has reiterated that Conservative campaign workers operated ethically.

During his Question Period interview, Giorno added that he was unable to offer details about Michael Sona, who resigned from his job with the Conservative campaign in Guelph soon after the robocalls scandal began to make headlines. Sona has denied involvement with any fraudulent calls and maintains he left his position because persistent media attention linking him to the affair made it difficult to do his job.

Court documents show the cellphone behind the misleading Guelph calls was registered to "Pierre Poutine" of "Separatist Street" in Joliette, Que., an obvious alias. Complaints about disingenuous calls, however, have emerged in ridings across the nation.

Both the Conservatives and opposition parties have welcomed an Elections Canada investigation into the scandal.

"Anyone concerned about the democratic process would be focused on identifying, persuading people and mobilizing people to vote," said Giorno. "Suppression of vote is a despicable, reprehensible practice and everybody ought to condemn it."