Liberal Leader Justin Trudeau, fresh off a commanding election win, has promised that Monday's vote will be the last under Canada's first-past-the-post electoral system.
After the election of a second-consecutive majority government with less than 40 per cent of the popular vote, calls for democratic reform seem to be gaining momentum. But some observers have suggested the idea may stall over public opinion and disagreement among those pushing for change.
The first issue, critics say, is that attempts to overhaul the electoral system have proved unpopular in Canada. When put to a popular vote, they have always failed.
In the second half of the last decade, three provinces seriously contemplated doing away with first-past-the-post systems in their legislatures. But the moment fizzled: Referendums in Prince Edward Island (2005), Ontario (2007) and British Columbia (2009) rejected change, with about 60 per cent of voters opting for the status quo in each case.
Mr. Trudeau appears prepared to bypass that stumbling block. The Liberal platform – which promises legislation on the issue within 18 months after study by an all-party committee – makes no reference to a referendum on a new voting system. And Mr. Trudeau's top adviser on democratic reform, political scientist Robert Asselin, says he thinks the issue may be too complicated to put to a vote.
"It's fair to say that the process led to misconceptions about what people were voting on," Mr. Asselin said of previous electoral reform ballots in Ontario and B.C. "It's really difficult to explain with all the options possible, to come up with a yes or no question."
But it remains unclear whether the Liberals have a mandate to legislate an end to first-past-the-post. Critics say that, while the party campaigned on the issue, it was only one part of an expansive platform – and that the Liberals only scored 39.5 per cent of votes.
David McLaughlin, a former deputy minister for democratic reform in New Brunswick, says that scrapping first-past-the-post across the country would require a referendum to be seen as legitimate. Unlike other types of policies, the choice between electoral systems is too significant to the country's democratic future to be handled exclusively by lawmakers, he argues.
"I fundamentally don't believe you can put this into effect without having a vote of the public," he said, adding that the provinces have always sought a referendum when attempting major electoral reform. "If you deviate from that standard, you better have a pretty damn good reason for it."
Mr. McLaughlin knows better than most how knotty it can be to push through big changes to the voting system. He authored a report for New Brunswick's Conservative government advocating a "mixed member proportional" system, in which voters would choose a local representative and then cast a second vote for a party, from which additional members would be seated. Germany and New Zealand have similar systems. But in 2006, before the province could put the proposal to a referendum, a new Liberal government was elected and scrapped the reform project.
Indeed, no country has successfully gotten rid of first-past-the-post through a popular vote since New Zealand did it in 1992, said David Schreck, who was secretary-treasurer of the "No" campaign in B.C.'s 2009 referendum.
The Liberals face a dilemma, Mr. Schreck argued: A referendum on proportional representation would probably fail, but electoral reform without a popular vote would be hard to sell to the public. "If [Mr. Trudeau] wants to sand-bag it, one way he could do it would be to hold a referendum, because it would be very unlikely to pass."
Many proponents of electoral reform feel that the cards are stacked against them in referendums, since changes such as proportional representation tend to benefit parties on the political fringe.
"We know from experience that partisans who don't want to lose power organize a lot of opposition," said Kelly Carmichael, executive director of Fair Vote Canada.
But Mr. McLaughlin thinks anything less than a referendum on the issue would be "a total cop-out."
"Electoral systems are too important to be designed by political scientists," he said.
Disagreement between activists and the government could be another roadblock to reform.
Mr. Trudeau and Mr. Asselin have promised to study all manner of systems and not put their thumbs too firmly on the scales, but both men prefer ranked ballots. Mr. Asselin has written about their benefits in the past. He argues that ranking tends to push political parties to the ideological centre, as they court second-place votes.
But ranked ballots irk hard-core reformers, who view them as a watered-down version of first-past-the-post. "We are definitely looking for action – my e-mail has been hopping," Ms. Carmichael said. "To electoral reformers, that only means proportional representation."