Canada’s chief electoral officer says he expects this election will cost taxpayers “several millions” more than prior years, thanks to legislation passed by the Harper government.

Speaking to CTV’s Power Play, Marc Mayrand said says he expects candidates will claim “several millions” more than past elections, due to changes brought in by the Conservatives’ Fair Elections Act.

However, he can’t yet predict an exact number, as this campaign -- 78 days -- is the longest in modern Canadian history.

“It’s difficult to say because this is historic and we don’t have a base line and it’s not clear how many candidates will be able to spend to the limit. But we expect certainly several millions in additional rebates,” said Mayrand.

Until the Fair Elections Act passed last year, every political campaign had a $25-million limit, regardless of a campaign’s length.

But under the new rules, there is no hard cap on the amount each campaign can spend. Parties’ spending limits are now increased if the campaign lasts longer than the 37-day minimum. For each additional day, parties will have their spending limit increased by 1/37th -- or $675,000 per day.

Parties are entitled to rebates of up to 50 per cent of their eligible election expenses; candidates up to 60 per cent. Those rebates are paid for by taxpayers.

Mayrand said he is “a bit concerned” that parties may claim ineligible expenses, given that they – unlike candidates -- they don’t have to submit supporting documents for their expense claims.

“Sometimes, yes, we would like to see some of the supporting documents. But unfortunately it’s not available at this point of time. We’ll see if future Parliament gives consideration to our suggestion in that regard,” said Mayrand.

In terms of additional costs to Elections Canada, Mayrand said this election campaign will undoubtedly be more expensive due to extended resources and staffing needs involved with a longer writ period. He said the organization will be able to determine that exact amount once it starts getting invoices.

There is some concern that other changes imposed under the Fair Elections Act may make it difficult for certain groups to vote this fall. Mayrand encouraged members of those groups, such as students, to vote early at one of four advanced polls, taking place on Oct. 9, 10, 11 and 12.

And if Canadians have any questions about their right to vote, Mayrand encouraged them to contact Elections Canada.