With one exception, the would-be leaders of the federal Liberal Party are betting on being able to lead the party back to government without any pre-election deals with the Opposition New Democrats to end vote splitting.
Vancouver-area MP Joyce Murray was the sole exception to the view among nine candidates at the first of five debates Sunday en route to the party choosing their next leader in April.
Former federal justice minister Martin Cauchon, a relative newcomer to the leadership race, said a strength of the Liberals is "we don't have any doctrine."
That leader faces the challenge of rebuilding the party base and somehow gaining political traction to drag the Liberals beyond their third-place ranking in Parliament behind the NDP and governing Tories.
During the two-hour debate before hundreds of Liberals at a downtown hotel, Mr. Cauchon said the Liberals are equipped to reach a "Canadian consensus" on issues that the NDP and Tories cannot. "Let's protect that great institution we have. Everything outside that today is pure distraction."
Former MP Martha Hall Findlay, who ran in the last leadership race, wryly wondered where the party's confidence had gone. "I am not an NDP (member). I am a proud Liberal. The answer for our party is to prove, not just talk about it, but prove we are the true alternative economic responsibility.
"We have to be confident. If we show Canadians we are the alternative, we will win."
After the debate, MP Justin Trudeau put the point most sharply, telling reporters he was "completely closed" to any such co-operation with the NDP.
Ms. Murray, a former cabinet minister in B.C.'s provincial Liberal government, has been proposing one-off deals with progressive parties to run single candidates in ridings where Conservatives won with less than 50 per cent of the vote to avoid centre-left vote splitting that might allow the Conservatives to win.
But the other candidates were dead-set against any such co-operation leading to a rare moment of conflict in the otherwise genteel two-hour debate at a downtown Vancouver hotel – a first chance to underline differences in which frontrunner Mr. Trudeau was largely spared any attack from his rivals.
"It's not enough to replace Stephen Harper. We have to replace him with a very, very clear vision of where we're going forward," Mr. Trudeau told Ms. Murray during a head-to-head exchange between the two.
The MP for the Montreal area riding of Papineau noted that the NDP would be against the kind of free trade he sees as necessary to create prosperity for the middle class. "What would electoral co-operation imply. What kind of values are we willing to jettison?"
"Justin that all sounds very good," Ms. Murray said in response, but asked for specifics of his plan to replace Mr. Harper, including how to avert vote splitting scenarios across the country, which some believe led to a Tory victory in a recent by-election in Calgary Centre.
"My plan is about reaching out to people across the country who are not polarized, who don't want to be voting against, who want to vote for by proposing a powerful option in the middle," said Mr. Trudeau.
"Stephen Harper and Thomas Mulcair would love nothing less than for the middle to disappear."
Beyond that encounter, however, there were few hard shots at Mr. Trudeau.
Marc Garneau, a former astronaut and former head of the Canadian Space Agency, ended the debate with a reference to leadership being a "product of life experience" that prompted reporters to later ask if it was a veiled shot at Mr. Trudeau, whom some have suggested lacks professional experience.
But Mr. Garneau shrugged off the suggestion in a post-debate scrum with reporters.
He said Liberals need to choose a leader with a proven track record and he would underline his mix of military, business and scientific experience without references to other candidates. "This is not a time to be modest," he said.
On the same issue, Mr. Trudeau spoke of the hard work to win over Canadians, suggesting he had been successful in doing that in Papineau – the riding he has held against tough challenges from the NDP and Bloc Québécois.
On stage and in the scrum, Mr. Trudeau called for a price on carbon, but ruled out taking a stand on a carbon tax, suggesting he wanted to see a debate on the issue. "Polluting cannot be free," he said. "There are multiple mechanisms with which we can approach that. I am not going to short-circuit a very serious policy discussion about the mechanisms we need to move forward."
The nine candidates in the race are Mr. Trudeau, Mr. Cauchon, Ms. Hall Findlay, Ms. Murray, lawyer David Bertschi, lawyer and academic Deborah Coyne, former Canadian Forces navigator Karen McCrimmon and technology lawyer George Takach. About 900 Liberals attended the debate.