If the Liberal leadership truly is Justin Trudeau's to lose, his eight opponents appear disinclined to help him lose it.
In the first all candidates' debate on Sunday evening, the Papineau MP delivered an assured performance that the others on the stage for the most part failed to challenge.
Montreal MP Marc Garneau and former Ontario MP Martha Hall Findlay also did well, giving the strong impression that this contest involves these three plus six also-runnings.
But nothing that happened in Vancouver Sunday night shook the strong probability that Justin Trudeau will be the next Liberal leader.
The debate was virtually devoid of policy substance.
Anyone who arrived looking for fresh ideas on trade, the environment, poverty or native concerns heard a great deal of empathy and calls for action, but very little in the way of what those actions should be, other than to listen and consult.
On the partisan front, the most direct challenge came from B.C. MP Joyce Murray, the only candidate who advocates co-operating with other parties to help defeat the Conservatives in 2015.
When Mr. Trudeau, who opposes the idea, insisted that "it's not enough to just replace Stephen Harper with somebody else" unless that somebody had a "very, very clear vision of where we're going forward." Ms. Murray retorted "if you want to replace Stephen Harper, where's your plan?"
His plan, Mr. Trudeau responded, involved "reaching out to people across the country." Which means whatever it means.
Apart from Ms. Murray – who has shown no evidence of emerging as a force in this campaign – all of the candidates made it clear there is absolutely no hope that Liberals and New Democrats will co-operate to defeat Mr. Harper in the next election.
"Where did your confidence go?" Ms. Hall Findlay asked Liberals who want to talk merger. "I'm not NDP. I'm a proud Liberal."
Those who hope progressive forces will combine to defeat the Conservatives in the 2015 election should shelve those hopes once and for all.
However, Mr. Trudeau did join with Mr. Garneau in promising that a Liberal government would replace Canada's first-past-the-post system of electing MPs with a preferential ballot, in which voters rank the parties, with the second choices of those who place last allocated until one candidate achieved a majority of support.
The Conservatives can be expected to leap on this proposal, warning that if they are relegated to a minority government in the next election, the NDP and the Liberals will combine to defeat them, form a coalition, and then change the electoral system to their advantage.
Deborah Coyne, one of the six marginal candidates in the race, appeared to confirm just that.
While ruling out co-operation with other parties before the election, she said, "after an
election it's a different ball game."
Mr. Garneau also took a shot across the Trudeau bow in his closing remarks.
The decision on choosing the next leader, he warned, is "the most crucial we've ever faced … the Liberal Party needs a strong leader. Leadership is the product of your life experience."
Mr. Garneau has a great deal more of that life experience than Mr. Trudeau.
But these were gentle jabs, and unlikely to dim the aura of inevitability that encircles Mr. Trudeau.
A single debate is just that.
There are four more to come, before the April leadership vote.
But any candidate who wants to challenge Mr. Trudeau's hegemonic lead needs to disrupt his image of unstoppability by more openly challenging his lack of experience and his vague commitments to "honest, open, strong conversations" that are devoid of content.
The eight can, of course, avoid such tactics in the interest of party unity and in hopes of gaining Mr. Trudeau's favour after he wins.
But then why did they run in the first place?