In a country unsatisfied with the status quo, complacency proved politically fatal.
It ended the reign of Stephen Harper, who came to office a decade earlier wanting to fundamentally change the role of government in this country, but in this campaign could not articulate a single bold thing he wanted to do if given one last term in power.
It proved the undoing of Tom Mulcair, who at the outset of the 78-day race appeared to have the best chance of replacing Mr. Harper in office – only to waste so much time trying to protect a lead that he wound up losing even Official Opposition.
And it gave an opening to Justin Trudeau, who by virtue of campaigning like a man with something to prove, bested two men who plainly did not consider him their equal.
There were many factors in the stunning rise by the Liberals from third place (and possible extinction, if this campaign went poorly) to government. And all of them – from the modest populism of taxing the rich and the courting of immigrant voters to the impact of the niqab debate and Mr. Trudeau just being a better retail politician than his opponents – will be untangled in the days and weeks ahead.
But the story of this campaign was set in the first few weeks – which, in retrospect, were the contest to determine whether Mr. Trudeau or Mr. Mulcair would be established as the primary change agent against Mr. Harper.
The Liberals knew that, if they fell further behind the NDP in the polls, they would be at risk of a death spiral as anti-Conservative voters fled them. The New Democrats somehow failed to grasp that the same thing could happen to them.
So, Mr. Trudeau showed up for the first leaders' debate with a fire under him, and was by far the most aggressive person on the stage. Mr. Mulcair awkwardly smiled a lot, tried to look reassuring, and barely registered – adding to a play-it-safe narrative that started when he refused to take reporters' questions on the day the writ dropped.
Seeking a clear differentiation point with the Conservatives on policy, Mr. Trudeau announced a plan to run budget deficits for three years in order to fund infrastructure and social spending. More or less simultaneously, Mr. Mulcair all but endorsed the Tories' fiscal policy by pledging to keep the budget balanced. For good measure, Mr. Mulcair joined Mr. Harper in attacking Mr. Trudeau for pledging to scrap the procurement of F-35 fighter jets – one of the more notoriously botched files under the Conservatives' watch.
Meanwhile, the Liberals were spending millions of dollars on unusually striking campaign ads – each of them with Mr. Trudeau energetically in motion as he rebutted his opponents' "not ready" charge against him. Seeking to keep their money in reserve for the campaign's second half, when they figured they'd still be in the lead (or close to it), the New Democrats ran almost no advertising at all.
It was not until September that the polls would show the Liberals surging ahead of the NDP in popular support. But the underlying perceptions that would pave the way for that were on the move in August. Toward the end, the New Democrats would try harder to strike a sharp contrast to the Tories, including by opposing a pan-Pacific trade agreement. But by then it was too late to make up for having assumed that only they would be taken seriously as change agents, because the head-to-head battle between Mr. Trudeau and Mr. Harper had been established.
The Tories were less guilty than the New Democrats of underestimating Mr. Trudeau; there is a reason they were still running attack ads against him, even when he was running third. But they overestimated something else: The ability of Mr. Harper to win over swing voters in the absence of much resembling a forward-looking agenda.
Rarely has an incumbent seeking another term offered less fresh reason to give it to him. Mr. Harper promised a smattering of tax credits and benefits and infrastructure expenditures, but it was marginal stuff relative to his previous policies. Beyond touting his record, almost his entire case for re-election came down to attacking the alternatives.
That was enough to keep most hard-core supporters on board. But the Tories lacked a compelling message to win over the slice of the electorate that put them over the top in the previous few campaigns. It was especially unclear what their candidates were supposed to tell constituents who were struggling economically or otherwise, and for whom "It would be even worse under the other guys" did not suffice. And their attempts to turn marginal issues into wedges, epitomized by taking aim at niqab-wearing women, apparently served mostly to further convince voters that Mr. Harper had overstayed his welcome.
Nothing in Mr. Trudeau's platform is exactly a panacea for all that ails the country, and most of it actually differs fairly mildly from what we have now. But it was more different than anything else on offer. And in how they packaged it, and how Mr. Trudeau presented himself, and in how their candidates outhustled Conservative opponents in particular on the ground, the Liberals were able to strike a tone that suggested ambition for something greater than what Canada is now.
The Liberals are certainly not immune to complacency. Having been swept to a majority in an election they started hoping just to get back in the game, there is some risk of the old arrogance creeping back in again. If they require incentive to guard against that, they need only remind themselves of their path back to power.