Starting with a sweep of the Atlantic provinces, the Liberals capitalized on what many Canadians saw as Mr. Harper’s heavy-handed style, and the party went on to capture 184 of the 338 seats in the next House of Commons. The unexpected rout occurred 47 years after Mr. Trudeau’s father, Pierre Elliott Trudeau, first swept to power. Justin Trudeau, who will be 44 on Christmas Day, will become Canada’s second-youngest prime minister and the first to follow a parent into office. While the Liberal Party had emerged on top in several polls over the past week, its lead was short of conclusive and Mr. Trudeau was an untested figure. There was no ambiguity, however, in Monday’s results. The Conservatives were reduced to 99 seats from 159 in the last Parliament, according to preliminary results. The New Democratic Party, which had held second place and formed the official opposition, held on to only 44 seats after suffering substantial losses in Quebec to the Liberals.
“More than a hundred years ago a great prime minister, Wilfrid Laurier, talked about sunny ways, he knew that politics can be a positive force and that is the message Canadians sent today,” Mr. Trudeau told supporters in Montreal. “Sunny ways, my friends, sunny ways, this is what positive politics can do.”
Speaking in Calgary, Alberta, Mr. Harper conceded defeat but vowed to supporters that the Conservatives would rise again. “The disappointment you all so feel, is my responsibility and mine alone,” he said. While Mr. Harper made no mention of his plans, the Conservative Party issued a statement saying that he had resigned as its leader.
The election became something of a referendum on Mr. Harper’s approach to government, which, in the view of his critics, has often focused on issues important to core Conservative supporters, mostly in the West, rather than to much of the population.