The Canadian political world has tilted on its axis.
The final slot for the 2015 campaign appears to have been filled with Justin Trudeau's easy ascension to the leadership of the Liberal party, a choice that makes the third party instantly relevant and, perhaps, a legitimate threat to come all the way back. Tom Mulcair has taken his New Democrats where they had to go, pragmatically moving to the centre, primed to try to take the next step to government, the last remnants of its socialist past shorn at a Montreal convention.
But maybe the three main slots have not been filled.
While the two main challengers to the Conservative government were inspiring the faithful in Montreal and Ottawa, all eyes now should be on the man who flew back to the capital on Sunday from his Calgary riding.
The Liberals and New Democrats have retooled. How will Stephen Harper respond?
Should Harper decide to seek another mandate from Canadians in an election that will happen no later than October 2015 - the prime minister has already mused about holding it earlier - he will be trying to break through a wall that many before him have hit, or saw coming too late.
In Trudeau, he will face a young man who has provided a major spark to the sleepy Canadian political landscape and, in Mulcair, a man who will campaign from a position of strength never before afforded a federal New Democrat.
Harper would be asking Canadians to allow him to move into his second decade as leader of this country. He will have passed nine years in office, through minorities and majorities, and would be taking his vision to the Canadian people for a fifth time.
Hubris might tell him he can easily slay the green Trudeau and the dogmatic Mulcair and he can again prosper as two parties that refuse to cooperate will brawl over the same pool of voters.
But as both a student of Canadian history and a man with strong political instincts, Harper knows of voter fatigue and a Canadian political predilection for seeking change for no reason other than just that they are tired of seeing the same face on their television screens. Jean ChrÃ©tien, who fired the Liberal audience on Sunday with an oldtime partisan speech, served 10 years but had to promise to hand off power during the 2000 campaign in order to secure his third majority.
Brian Mulroney, even with two majorities, lasted just short of nine years.
At the provincial level, the same best-before date appears to work. Dalton McGuinty announced he was stepping down almost nine years to the date he was sworn in as Ontario premier.
In Quebec, Jean Charest was defeated after nine years in office.
Should Harper decide to run again, he will have passed Louis St. Laurent, Robert Borden and Mulroney by the time the campaign starts and would already have become the sixth-longest serving prime minister in Canadian history before seeking another four years.
It would be a huge risk for Harper, even should he be fortunate enough to keep the Canadian economy on the rails until then.
That risk could be multiplied by the Trudeau challenge if the new Liberal leader keeps his pledge to remain firmly on the high road, keeping his promise to make himself the reincarnation of a sunny Wilfrid Laurier.
"Canadians want to be led, not ruled," Trudeau said.
"They are tired of the negative, divisive politics of Mr. Harper's Conservatives and unimpressed that the NDP, under Mr. Mulcair, have decided that if you can't beat them, you might as well join them.
"We are fed up with leaders who pit Canadians against Canadians, west against east, rich against poor, Quebec against the rest of the country, urban against rural."
Conservatives will attack him, possibly at his peril.
The NDP says its battle is with Harper, but Peter Julian, the British Columbia MP who attended the Liberal finale, said Trudeau has aligned himself with Harper on the Keystone XL pipeline, Senate reform and the Chinese government intervention in the oilpatch.
"We have young members, they have six-month tire-kickers, one-time voters who are over 50 and nostalgic for his father," Julian said.
Trudeau may be difficult to wound, and both Conservatives and New Democrats may be waiting in vain for a selfinflicted one. It will likely be a year before Trudeau and the party craft policy that his rivals can take aim at.
Still, the outlines of the 2015 campaign have become much clearer.
What remains unclear is who will be leading the Conservatives.
Tim Harper is a syndicated Toronto Star national affairs writer who can be reached at [email protected].