CHARLOTTETOWN -- Canadians are expected to learn late Tuesday whether the cradle of Confederation will give birth to one of the country's first versions of proportional representation.

Alongside an election to pick a provincial government, voters will be asked to answer the question: "Should Prince Edward Island change its voting system to a mixed member proportional voting system?"

The winning side must receive more than 50 per cent of the votes cast and win a majority of votes in at least 60 per cent of the ridings.

A "No" vote would mean the continuation of the 27-seat legislature chosen by the first-past-the-post system.

A "Yes" vote would lead to a switch where voters choose 18 legislators in redrawn electoral districts, while also casting ballots for nine other legislators from lists the parties create.

These "party list" seats would then be assigned proportionately based on the popular vote each party received on the second part of the ballots.

If the Island votes in favour, P.E.I. may become Canada's first to bring in a partial proportional representation system, depending on how quickly the Island's politicians move to finalize details of the system.

Quebec's new CAQ government, which campaigned in part on the issue, has also said it would move to adopt a mixed member proportional system before the next provincial election in 2022.

Voters in British Columbia rejected making such a change in December.

Prime Minister Justin Trudeau promised to abolish the first-past-the-post federal voting system during the 2015 election, but he later abandoned the plan, saying Canadians were not eager for change.

Political scientist Don Desserud says it's difficult to assess which side in Prince Edward Island has the upper hand going to the polls.

He said the referendum has been overshadowed by the wider provincial campaign -- with the possibility of a surge by the third-party Greens capturing public attention.

Desserud says there's a risk that many voters in the general election may find themselves making up their minds on the referendum without having carefully considered the issue.

The University of Prince Edward Island professor says that may play out in favour of the "Yes" side if there's a general mood for change, but it may also benefit the "No" campaign if voters feel uncertain and decide to opt for the status quo.

"There's not a lot of interest in the referendum itself. The electorate are not all that excited one way or another," he said in a telephone interview.

"If they're not interested, it raises the question of 'How will they vote?"'

During the recent leaders' debate, the leaders of the Green party, the NDP and the Progressive Conservatives said they personally favoured the "Yes" option, while Liberal Premier Wade MacLauchlan declined to give a personal preference.

However, all four leaders have committed to honour the result of the vote.

The two main groups that campaigned on the issue received $75,000 in public funding each to deliver their message.

About 1,200 people attended public information sessions provided by the referendum commissioner to explain the two systems between Feb. 1 and the end of March.

Advocates of proportional representation on the Island argued a large part of the population has been under-represented in past legislatures, which have often swung with lop-sided results to either the Liberal or Conservative parties.

Brenda Oslawsky, a spokeswoman for the "Yes" campaign, said, "with a proportional voting system, the vast majority of people will elect someone with their vote ... everyone's vote is at the table."

The "No" side has argued the proposed system leaves too many questions unanswered, such as how parties will choose their lists of candidates -- and warns the system risks creating a series of unstable, minority governments.

John Barrett, a spokesman for the "No" campaign, said there's also worry proportional representation will weaken the representation of rural P.E.I.

He said he's hopeful his side's message has reached many Islanders.

However, Barrett said he's also worried that some voters will vote for a shift from the status quo without considering the issues at play.

"My concern is that we've seen a propensity of voting for change lately without people really understanding the ramifications of what change can bring," he said in an interview.

-- By Michael Tutton in Halifax.