And the governing Conservatives appear best positioned to reap the benefits of the unforeseen spending-room bonanza, which comes courtesy of a little-debated provision in the election bill.
The rule change allows individual candidates — and national parties — to inflate their spending cap by a pro-rated amount whenever a campaign extends beyond the 37-day minimum.
Prime Minister Stephen Harper announced Sunday that byelections have begun in three vacant Ontario ridings — but that voting day for the three isn't until Oct. 19, the likely date of a full general election.
The resulting 169-day campaigns mean that byelection candidates in Ottawa West-Nepean, Peterborough and Sudbury collectively can spend into the millions. So can their respective national parties.
And those candidate expenses are eligible for a rebate of 60 per cent from Elections Canada.
Pierre Poilievre, the minister responsible for democratic reform, was not available for an interview this week but his office expressed no concerns about the massive campaign expense caps.
"This increase applies equally to all candidates seeking election in an electoral district, as well as to other actors such as third-party advertisers," said the emailed response, attributed to the minister.
"All campaign funds must only come from eligible sources and be in compliance with strict contribution limits under the Canada Elections Act. Each candidate campaign will need to determine how to allocate their campaign funds to achieve the most impact."
Rules that increase spending limits would appear to favour the governing party.
The latest financial reports filed with Elections Canada show the Conservatives pulled in $6.3 million in the first three months of 2015 — more than the Liberals ($3.9 million) and NDP ($2.3 million) combined.
Elections Canada has posted preliminary byelection candidate spending caps, based on the preliminary list of eligible voters, for each of the three ridings in play.
The Peterborough electoral district has expense limits of $508,682, compared to the $95,208 each candidate was able to spend over 37 days in the 2011 general election.
Sudbury's preliminary cap is $446,064 over the 169-day campaign, up from $72,019 in 2011, while Ottawa West-Nepean's cap is $467,778, compared with $82,874 four years ago.
While individual candidates would have a difficult time raising that kind of money, Elections Canada says there is nothing to stop a national party, or other deep-pocketed riding associations, from transferring funds into an electoral district.
Moreover, the parties themselves have massively expanded byelection spending caps, thanks to the new pro-rated system.
Each party can spend $431,270 in Peterborough, $376,208 in Ottawa West-Nepean and $334,101 in Sudbury.
The high spending limits for the three Ontario byelections will allow a party with a deep war chest to blanket much of the province for the next four months with advertising that's subject to hefty Elections Canada rebates.
And should Harper call a general election in early September for Oct. 19 as expected, all those byelection races are suspended and their expense limits will be reset — allowing even further spending beyond the posted byelection caps for parties with the financial wherewithal to do so.
The Peterborough seat opened up when Dean Del Mastro, Harper's former parliamentary secretary, resigned last Nov. 5 after being convicted on three counts of violating the Canada Elections Act. He has yet to be sentenced but the Crown is seeking jail time.
Harper's hands were tied somewhat by election rules that state a byelection must be called within six months of a seat becoming vacant, forcing him to set in motion the Peterborough vote last weekend.
It was the prime minister's choice to call all three vacancies at once, and to make byelection day the same date as an anticipated Oct. 19 election.
Former New Democrat MP Glen Thibault abandoned his Sudbury seat in mid-December when he quit to run for the Ontario Liberals in a provincial byelection. The machinations over Thibault's Liberal nomination are the subject of a police probe.
Former foreign affairs minister John Baird quit his senior post in the Harper cabinet on Feb. 3 and vacated his Ottawa West-Nepean seat in mid-March.
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