Justin Trudeau, 43, holds a young child during a campaign stop at a restaurant in Welland, Ontario, on Oct. 14. (Paul Chiasson/Canadian Press via AP)

On Oct. 19, the Canadian electorate delivered a stunning victory to the Liberal Party, led by Justin Trudeau. When the campaign started in August, few people would have put money on the Liberals even coming in second. And yet they resoundingly defeated Stephen Harper’s Conservative Party, which had held power for the previous nine years.

The Liberals won 184 seats with just shy of 40 percent of the vote, which is the kind of big win regularly delivered by a “first past the post” system — whoever gets the most votes in a district wins the seat. The incumbent Conservatives won 99 seats with 32 percent of the vote, while the left-of-center New Democratic Party (NDP) won 44 seats with 19.7 percent. It was an incredible reversal of fortune for the two parties of the left: The Liberals had entered the campaign with just 36 seats while the New Democrats held 95.

Between the two smaller parties, the Green Party managed to retain its single seat with 3.5 percent of the popular vote. The separatist Bloc Quebecois, which only enters races in Quebec, won 10 seats with 4.7 percent (19.3 percent of the Quebec vote).

As can be seen in the figure below, the NDP started the race with an unambiguous lead. But by a third of the way through the campaign, NDP had lost that lead. The three main parties were in a dead heat. A week and a half after that, mid to late September, the tide turned for good. The Liberals took the lead and stayed there.

So what happened?


Vote intention in the 2015 Canadian Election campaign Source: Local Parliament Project

 

Many explanations have been circulating since the election, including the role of leaders, the impact of particular campaign policy announcements such as the Conservatives’ proposed ban on the niqab in citizenship ceremonies, and the role of various scandals.

To better understand the election, we conducted what we believe is the largest public opinion study ever in a Canadian election, surveying more than 37,000 Canadians (on average 700 every day) between Aug. 26 and Oct. 18, the day before the election.

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Two factors seem particularly important.

First, voters substantively changed their minds about the leaders, particularly the Liberal leader, Trudeau. The second was an effective coordination (and perhaps an “over-coordination”) of left-wing voters.

1. Leadership

Our project asked respondents to evaluate each party leader on four traits or phrases. Two were “trustworthy” and “really cares about people like me,” for a sense of how they evaluated character. The other two were “provides strong leadership” and “intelligent,” for impressions of competence.

Amanda Bittner’s great cross-national study of leadership effects (that is, the influence of particular political leaders and their traits and personality on opinion and behavior) suggests that voters on the left privilege character while voters on the right privilege competence. Voters in the middle presumably like a bit of both.

Harper scored low on trustworthiness and empathy but performed well on strength of leadership and intelligence—making those the right qualities to attract conservative voters.

Thomas Mulcair, the leader of the NDP, was considered strong and intelligent — but voters simply didn’t regard him as empathic, which was a problem in attracting voters on the left.

For most of the campaign, only 1 in 5 Canadians thought that Trudeau showed much strength of leadership. But as the figure below shows, he did well in several debates — and in the last three weeks of the campaign the share of Canadians who regarded him as a strong leader increased by 50 percent. His vote share increased at roughly the same time.


Trudeau leader evaluations and Liberal Party vote share Source: Local Parliament Project

2. Strategic voting.

A second factor in the election was strategic voting — that is, voters casting ballots for their second choice if they believed that candidate had a better chance of beating their least preferred candidate (usually the Conservative). Several groups made an organized effort — through Web sites such as strategicvoting.ca and votetogether.ca and social media — to encourage citizens to coordinate and oust Harper’s Conservative government.

Central to the logic of strategic voting is the ability of individuals to fairly accurately predict the outcome. In other words, one needs to have a realistic expectation of outcomes in order to know for whom to cast a strategic vote and when it is necessary to do so.

We asked respondents to our survey to tell us the chances they thought each party had of winning the most seats in the election. These numbers sometimes don’t sum to 100. But the most important thing is the relative standing of the parties. Responses over the 11 week campaign are in the figure below.


Caption: Trudeau leader evaluations and Liberal Party vote share
Source: Local Parliament Project

When it comes to expectations, Harper would have wanted to see confusion on the center-left about the respective chances that either the Liberals or the NDP could form a government. Trudeau was instead hoping voters would have a clear picture of the viability of Liberals coupled with a decline of the NDP. These are of course self-reinforcing dynamics.

Our data indicate the Trudeau got his wish. As the campaign wore on, greater numbers of Canadians moved to the Liberals, in part because they began to view Trudeau as indeed being “ready” (or a “strong leader”) — despite the Conservative ad campaigns.

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For roughly the first half of the campaign, most citizens gave the NDP a greater than 50 percent chance of winning the most seats.

But that started to turn as opinion swung toward the Liberal Party. By early October, a couple of weeks out from the election, expectations that the Liberals would win a plurality of seats began to take off. Both the NDP and the Conservatives dropped rapidly in citizen expectations. Voters coalesced around the Liberal Party as the one viable alternative to the Conservatives.

The election results bear this out. Many observers were surprised at the size of the Liberal majority and at the fact that many talented NDP candidates and incumbents lost to Liberal candidates, even rookies. Here’s how we read these races, in the light of our data on expectations and the effects of the Canadian electoral system: center-left voters were so determined to block a Harper victory that, once they realized the NDP would not get enough votes to form a government, they swung toward the Liberals even more than was necessary.

Our post-election survey of more than 10,000 Canadians indicates that even among Liberal voters, a substantial number (just over 25%) would have preferred a minority Liberal government. In other words, this time, the left may have over coordinated, after several elections where commentators had lamented the lack of coordination.

Peter Loewen is an associate professor in the department of politics and Munk School of Global Affairs and the University of Toronto.

Daniel Rubenson is an associate professor in the politics department at Ryerson and an affiliated researcher at the Research Institute of Industrial Economics.