Liberal leader and incoming prime minister Justin Trudeau makes his way to the stage with wife Sophie Gregoire at Liberal party headquarters in Montreal early Tuesday, Oct. 20, 2015. THE CANADIAN PRESS/Paul Chiasson

OTTAWA - Just watch him.

A Trudeau is headed back to 24 Sussex Drive, completing the first father-son dynasty in Canada's federal government history, and vanquishing the Conservative leader who came to politics hoping to remake the Trudeau vision of Canada.

Justin Trudeau will become Canada's 23rd prime minister after his party steamrolled to a stunning majority victory Monday night — the culmination of the longest and most expensive general election in modern times, and one of the most bitter.

"You can appeal to the better angels of our nature and you can win while doing it," a hoarse Trudeau told a delirious Liberal crowd in Montreal after invoking the "sunny ways" of Sir Wilfrid Laurier, a Liberal prime minister from the dawn of a previous century.

"I hope it is an inspiration to like-minded peoples to step up and pitch in, to get involved in the public life of this country and to know that a positive, optimistic, hopeful vision of public life isn't a naive dream, but can be a powerful force for change."

The Liberal party, which appeared poised to claim 184 seats in the newly expanded 338-seat House of Commons, becomes the first ever to vault directly from third party status to government. Even the Liberals' internal pollster, who foresaw a majority, hadn't imagined a total so high.

And Trudeau, 43, returns to his childhood home, where he was the first-born of Pierre Elliott Trudeau, who served as prime minister for almost 16 years before retiring in 1984.

Trudeau faced more than two years of Conservative attack ads before defeating Harper, including a barrage of "just not ready" ads so ubiquitous that school-age children could recite them.

Notwithstanding his appeal to Canadians' "better angels," the new prime minister-elect gave a lengthy denunciation of what he called the politics of division and fear, including a defence of veiled Muslim women who became an unlikely wedge issue during the campaign.

"Canadians have spoken," Trudeau said.

"You want a government with a vision and an agenda for this country that is positive and ambitious and hopeful. Well, my friends, I promise you tonight that I will lead that government … I will be that prime minister."

During the October crisis of 1970, Pierre Trudeau famously told an inquiring reporter "Just watch me," when asked how far he would go in limiting civil liberties to combat separatist terrorists. The elder Trudeau went on to shape much of the modern Canadian state that Prime Minister Stephen Harper came to power in 2006 in part to re-make.

With the magnitude of the Conservative party loss still sinking in, the Conservative leader — who called the extraordinarily long, 78-day election on Aug. 2 after almost 10 years in power — is stepping down as party leader, according to a statement from party president John Walsh.

"The prime minister indicated that he will continue to sit as a member of Parliament and asks that a process to both select an interim leader and initiate the leadership selection process in our party begin immediately," says the Walsh letter.

Harper did not announce his resignation in a concession speech to party faithful in Calgary, stating only that the "disappointment you also feel is my responsibility and mine alone."

But he offered gracious congratulations to his younger opponent.

"While tonight's result is certainly not the one we had hoped for, the people are never wrong," said the prime minister, adding he had called Trudeau and "assured him of my full co-operation during the process of transition in the coming days."

NDP Leader Tom Mulcair, who'd aspired to lead Canada's first NDP federal government, instead lost the party's hard-won 2011 grip on official Opposition status. That role will fall to the Conservatives.

Mulcair, however, managed to hold on to his Montreal seat despite a tough Liberal challenge.

Green party Leader Elizabeth May was also re-elected on Vancouver Island, while Bloc Quebecois Leader Gilles Duceppe went down to defeat.

The New Democrats were decimated, dropping to 42 seats after entering the election with 95. Mulcair had a tough fight just hanging on to his own Montreal riding.

The shocking Liberal onslaught opened on the East Coast, where Liberals swept all 32 Atlantic Canada seats, before rolling into Quebec and Ontario and Manitoba.

With the polls simultaneously closing from the Quebec-New Brunswick border all the way to the foothills of the Rocky Mountains, the scale of the Liberal charge became clear as the ballot counting commenced: The Liberals finished just shy of 40 per cent of the popular vote and knocked off Conservative and NDP heavyweights across the country.

Trudeau romped to victory in his gritty Montreal riding of Papineau as the Liberals restored their Quebec fortunes to help anchor the surprising victory.

Finance Minister Joe Oliver, Immigration Minister Chris Alexander, Fisheries Minister Gail Shea, Veterans Minister Julian Fantino and Aboriginal Affairs Minister Bernard Valcourt were among the Conservative cabinet ministers rejected by voters.

NDP stars including deputy leader Megan Leslie and foreign affairs critic Paul Dewar also fell to Liberal challengers. Olivia Chow — her late husband, Jack Layton, led the NDP's so-called "orange crush" in 2011 — succumbed to Liberal juggernaut Adam Vaughan in downtown Toronto.

"I congratulated Mr. Trudeau on his exceptional achievement both for him and his party," Mulcair said in a concession speech in Montreal.

"In this campaign, Mr. Trudeau made ambitious commitments to Canadians and Canadians will have high expectations for their next Parliament."

Harper hoped to become the first prime minister since Laurier in 1908 to win four consecutive mandates. However with all opposition parties vowing not to work with him after Monday's election, it was apparent that only a very strong Conservative minority or a Tory majority would keep Harper on as prime minister.

It was never even close.

For the 2015 election, there was no longer a blackout on transmitting voting results while polls were still open in other parts of the country — a ban that had become impossible to enforce in the age of the Internet. The change of government was evident before the polls even closed in B.C.

The Conservatives held 159 seats in the 308-seat House of Commons, the NDP had 95 and the Liberals held just 36, with another 18 seats either vacant, held by Independents or shared between the Green party (two seats) and the Bloc Quebecois and a splinter group.

Due to population growth, 30 new seats were added this election, including 15 in Ontario, six each for Alberta and British Columbia and three more for Quebec.

Some 3.6 million Canadians cast ballots during the four-day advance polling period on the Thanksgiving long weekend — an increase of 71 per cent over the 2011 election, when only three days of advance polls were held.

That increased turnout, however, did not appear to carry into the main event, despite long lines at polling stations in many parts of the country. Just 61.4 per cent of eligible electors cast a ballot in 2011, up marginally from the 58.8 per cent in 2008 — the lowest ever in a federal election.

— With files from Murray Brewster, Jim Bronskill, Jennifer Ditchburn, Bill Graveland and Chinta Puxley

News from © The Canadian Press, 2015