Murray says she believes Liberals, New Democrats and Greens should have the option of conducting run-off nominations to choose a single candidate in tightly contested ridings where a united progressive front would guarantee defeat of the ruling Tories.
She is the first contender to broach the controversial idea, which is consistent with her broader pitch that she is a collaborative politician who brings unique perspectives and attributes to the race.
"One of the things that I bring is just the full spectrum of the Canadian experience," the 58-year-old told The Canadian Press in an interview shortly before officially announcing her leadership campaign Monday.
"I'm an immigrant (from South Africa), a woman, a mother who went back to school while building a business ... and then I pull that together in a way that is typical of women, which is working with people, collaborating, co-operating, finding a way forward and then delivering."
Murray noted she is also the only contender so far with any decision-making experience in government, having served as a cabinet minister in British Columbia.
She said her background leaves her uniquely positioned to balance environmental sustainability and economic growth. She's a former environment minister, but also a successful businesswoman, who co-founded with her husband a reforestation company that now employs 600 full-time and 600 part-time employees in five countries and which planted its billionth tree last year.
At a news conference to launch her campaign, Murray also touted her credentials as a westerner, although she would not directly slag leadership front-runner Justin Trudeau for a two-year-old television interview in which he lamented the sorry state of the country when run by Albertans rather than Quebecers.
"I am not planning to give the Conservatives their next three or four attack ads in this campaign," she said, adding that she doesn't accept the notion that the race will be a boring coronation unless contenders are "tackling each other in the boxing ring."
Still, Murray criticized the party for its history of choosing leaders who hail either from Quebec or Ontario.
"That is part of the old culture of the party that has led us into the trouble our party is in today. So those kinds of ideas have to change. It's insulting to the 15-20 million Canadians that don't live in Ontario or Quebec."
Murray is decidedly to the left of most other leadership contenders, who've been positioning themselves as business-friendly, "blue" Liberals.
She's an unapologetic advocate of legal marijuana and an ardent environmentalist who favours a carbon tax, although she's open to suggestions of better ways to put a price on carbon.
But her proposal for co-operation with other parties is bound to be the most controversial.
Murray sees the idea as a way to get rid of the Tories and start serious reform of the first-past-the-post electoral system to ensure future elections more accurately reflect each party's popular vote.
The current system is not only unrepresentative, she said it "rewards demonizing other parties, it rewards dirty tricks in elections, it rewards toxic, polarized, divisive behaviour in Parliament and it's turning Canadians off.
"If our electoral system is broken, we need to have a conversation about what's more suitable for Canada. But clearly, we are never going to have that conversation with Stephen Harper in the driver's seat."
To make sure Harper is ejected, she said progressive voters need to be able to unite behind a single candidate in some ridings.
Murray wouldn't impose the idea of co-operation; she'd ask Liberals to endorse it at their next convention, then leave it to local riding associations to decide whether to use it or not. It would be a one-time tactic only for the 2015 election.
She stressed she is not proposing a merger with the NDP or any other party.
Still, Murray's openness to co-operation with other parties is risky. It's bound to spark a backlash from some Liberals who believe it's a defeatist admission that the party can't beat the Tories on its own.
Rival contender David Bertschi immediately denounced the proposal as sacrificing "Liberal values for political expediency." The Ottawa lawyer said a Liberal party led by him would run a full slate of candidates.
But the proposal could also help set Murray apart from the pack chasing presumed front-runner Trudeau, who is widely thought to have a huge head start in the race.
Trudeau rejected the idea of co-operation with other parties, saying in Montreal Monday evening that he intends to run Liberal candidates in every riding if he's elected leader.
Even if Liberals were to embrace the idea, however, there's no guarantee the NDP and Greens would be willing to go along. NDP Leader Tom Mulcair has adamantly ruled out any co-operation with Liberals, although Green Leader Elizabeth May has been more open to the notion.
On other issues, Murray said:
— "We have to put a price on carbon, there's no way around that." She said B.C.'s carbon tax has proved to be an effective way to reduce greenhouse gas emissions without hurting the economy but "if there is a better way, I'm open to it."
That said, Murray added she doesn't see tax as a dirty word. "When we talk about tax as if tax is a four-letter word, I disagree. ... It's a tool for accomplishing the goals of society and protecting the public interest."
— She supports continued development of Alberta's oil sands, although "they have to be developed in a more sustainable way."
— She supports a pipeline to move Alberta's energy resources to eastern Canada. But she's opposed to two pipeline proposals to move unrefined oil sands bitumen through B.C. for shipment to China.
"I think that those pipelines represent a huge investment and long-term commitment to a bad business model," since it relies on subsidized oil sands development in an environmentally unsustainable manner and amounts to exporting the value-added refinery jobs.
— She favours legalizing marijuana. "Why do we want to put more young people in jail for a cannabis offence? Why do we want to continue supporting it being controlled and regulated by criminals? I think it's time to legalize marijuana, regulate it, control it, tax it."
— She would, as prime minister, ensure women were appointed to at least 40 per cent of the positions on federal agencies, boards and commissions, including the federal cabinet.
Murray joins a crowded field of contenders, including Trudeau, Bertschi, former Toronto MP Martha Hall Findlay, Toronto lawyer Deborah Coyne, retire Canadian Forces Lt.-Col. Karen McCrimmon, Vancouver prosecutor Alex Burton and David Merner, former president of the party's B.C. wing.
Montreal MP Marc Garneau, is set to join the contest Wednesday, while Toronto lawyer George Takach is to follow Thursday. Ontario government economist Jonathan Mousley is still hoping to enter if he can raise the stiff, $75,000 entry fee.
So far, only Trudeau and Coyne have officially registered as candidates, filed the required nomination papers and paid the first of three $25,000 instalments on the entry fee.
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