What is the ‘alternation’ theory and will Ontario continue the trend on election day?

Prime Minister Mark Carney, right, and Ontario Premier Doug Ford take part in the First Minister Meeting at the National War Museum in Ottawa on Friday, March 21, 2025. THE CANADIAN PRESS/Adrian Wyld (The Canadian Press)

As Canadians inch closer toward election day, political experts are watching closely to see if Ontario will continue a trend of split-ticket voting, choosing one party to govern at Queen’s Park and a different one to form government in Ottawa.

Often referred to as the “alternation theory,” experts say Ontario has a long history of voting for one party provincially and another federally.

“Since 1867, about 78 per cent of provincial elections in Ontario have been won by a party ideologically different from the federal governing party,” Semra Sevi, assistant professor of political science at the University of Toronto, told CTV News Toronto. “Since 1943, that figure exceeds 90 per cent.”

Despite this trend, there has been overlap between federal and provincial governments in the past, including most recently in 2015 when former prime minister Justin Trudeau was elected at the same time Liberal premier Kathleen Wynne was in power in Ontario.

Political experts say Ontario’s history of split-ticket voting has less to do with allegiance to a party and more to do with how voters view individual leaders.

“Leadership perception appears to matter more than policy,” Sevi said. “Voters evaluate federal and provincial leaders independently. This is reflected in the weak alignment between the electoral performance of federal and Ontario Liberal and Conservative parties.”

Sevi added that it has become apparent that there is minimal party loyalty between elected officials federally and provincially, noting that Premier Doug Ford has been “publicly friendly” with the Liberals while not stepping in to campaign for his federal counterpart.

Economic stability over party loyalty

As U.S. President Donald Trump continues to flip-flop on tariff measures, more uncertainty looms for Ontarians and many Canadians alike.

CTV News’ political commentator Scott Reid said when it comes to Ontario voters, they are prioritizing perceived stability in party leaders.

“While it appears that people are voting for different leaders and different party banners federally and provincially in Ontario, I think the interesting phenomenon we’re witnessing in this election again is that voters are actually looking for — and rewarding — the same core offering,” he said.

That offering, he says, includes stability, reassurance, and a focus on job and economic security.

“They reward Doug Ford because they see more of that stability,” Reid said. “Then they will reward the very same thing in Carney and the Liberals because they see more of those same attributes there.”

Reid insists this isn’t about Ontarians trying to balance out power at Ottawa and Queen’s Park but rather placing an emphasis on finding consistent values in different leaders.

“They have priorities, they go looking for those priorities in places they vote,” Reid said. “And so, they see those characteristics in Doug Ford, and now they see them more apparent in Mark Carney.”

Can the Liberals secure another 4 years?

The latest Nanos poll, commissioned by CTV News and the Globe and Mail, show the Liberals have a four-point advantage on the final day of the campaign, backed by strong support in the Atlantic region, Ontario and Quebec.

Meanwhile, the the Conservatives continue to remain dominant in the Prairies.

Reid predicts Ontario’s trend of vote-splitting could spell big gains for the Liberals come election day.

“I think Carney is going to overperform even expectations in Ontario,” he said. “I think we’re going to see a massive majority of seats federally go to the Liberal vote.”

With files from CTV’s Phil Hahn

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