The former Chretien-era cabinet minister, who filed his nomination papers just hours before Sunday's midnight deadline, said he took his time deciding whether to take the plunge because he knows that seeking to eventually run the country is a huge commitment, not a "popularity contest."
"It's never too late to take the right decision," the 50-year-old told The Canadian Press.
"One of the advantages I have is experience," he added, noting that he led the party's Quebec wing before becoming an MP in 1993 and eventually a cabinet minister and Quebec lieutenant for then-prime minister Jean Chretien.
"I've been there 10 years (in government) ... so I know pretty well government machinery. I know that leading the party and leading the country, it's not a popularity contest. Sometimes you have to take strong decisions and take strong stance.
"And I know what it means. I've been there, done that."
The reference to what's at stake being more than a popularity contest appears aimed at presumed front-runner Justin Trudeau, eldest son of Liberal icon Pierre Trudeau and the party's undisputed celebrity. Opinion polls have put the high-profile 41-year-old Montreal MP miles ahead of all competitors in terms of public visibility and popularity and have suggested he could vault the third-place party back into contention for power.
Justin Trudeau launched his campaign in early October; the other seven officially confirmed contenders have been stumping the country since at least November.
Cauchon, whose candidacy was approved by the party Tuesday, said the Liberals' new supporter category — allowing anyone who professes support for the party's principles to vote for the next leader, not just card-carrying party members — makes the leadership contest a "discussion with Canadians as a whole." And there's still plenty of time to make his mark before the new leader is chosen on April 14.
He said he already has some support among caucus members and other high profile Liberals — including rumoured backing by Chretien's daughter, France Desmarais — but said their names will be announced in due course.
Cauchon retired from politics in 2004, but a 2011 comeback attempt in his old Montreal riding of Outremont was thwarted by Tom Mulcair, now NDP leader, as an unprecedented tidal wave of support for New Democrats swept Quebec and vaulted the NDP into official Opposition status for the first time in its 50-year history.
Cauchon dismissed suggestions his failure to beat Mulcair will be a liability among Liberals looking for a leader who can overtake the NDP and take on the ruling Conservatives.
"To tell you that the last election was a storm is probably an understatement. You know, when an NDP member could win the riding without going in his riding and spending two weeks in the (United) States during the campaign, it tells you that wasn't something normal," he said.
It was even harder to buck the Quebec tide in Outremont because Mulcair was already the incumbent MP, he added.
"I knew it would be tough before getting into that campaign. But I did it because I wanted to show people I was a real Liberal and I can roll up my sleeves when it's tough."
Others, including late Quebec premier Robert Bourassa, have led their parties despite personal defeat in their ridings, he observed. Indeed, Cauchon himself lost in his first election attempt in 1988, when he ran against Conservative Prime Minister Brian Mulroney, in the eastern Quebec riding of Charlevoix, before going on to win in Outremont in 1993.
"To lose the battle is not to lose the war ... It means nothing," he maintained.
Should he win the leadership, Cauchon said he'd likely take a few months to travel the country and engage Canadians before seeking a seat in the House of Commons by asking an incumbent Liberal to step aside temporarily — much as Chretien did after winning the party's leadership in 1990.
However, in the next election, Cauchon said he'd probably run again in Charlevoix, where he was born. The riding is currently held by the NDP.
"Two leaders are not going to run in the same riding, obviously," he said, ruling out a re-match with Mulcair in Outremont.
"I believe one of the challenges we have as a party is to go back in Quebec. That is key," he added.
Cauchon is the third Quebec candidate in the race, along with Trudeau and Montreal MP Marc Garneau, Canada's first man in space.
He is entering a race which has taken on a pronounced right-wing tilt, with Trudeau calling for greater openness to foreign investment by state-owned enterprises in Canada's oil sands, Garneau pitching wide-open competition in telecommunications and former Toronto MP Martha Hall Findlay calling for an end to supply management in the dairy industry.
Billing himself as "fiscally responsible and socially progressive," Cauchon said both the left and right wings of the party are now represented in the leadership contest and that's a good thing.
"The Liberals are more pragmatic (than the Tories and NDP) and we have two wings, the right and the left, and when the two talk together, this is when we're very strong."
Among other things, his campaign will focus on restoring Canada's place in the world as a respected middle-power and honest broker, targeting investments in economic development and supporting regional development and the arts.
As Chretien's justice minister, Cauchon gained a reputation as a progressive by spearheading moves to decriminalize marijuana and legalize same-sex marriage. The latter was eventually implemented by Chretien's successor, Paul Martin, but the former was scotched by Prime Minister Stephen Harper's government.
However, Cauchon isn't prepared to move as fast or as far on marijuana as rank and file Liberals, who endorsed full legalization, regulation and taxation of pot at their last convention a year ago. A number of Cauchon's rival candidates, including Vancouver MP Joyce Murray, Hall Findlay and Toronto technology lawyer George Takach have similarly endorsed that position.
Cauchon said Canada is signatory to international conventions on marijuana that must be respected. Moreover, while decriminalization is a good first step, he suggested Canadians aren't ready to go further than that.
"It's a question of the evolution of society. I believe society is ready for my (decriminalization) bill today. Maybe 10 years ago I was 10 years ahead of my time."
On another issue that is proving contentious in the contest, Cauchon said he supports construction of a pipeline to carry raw bitumen from Alberta to ports in British Columbia. But he said it can only be done by respecting both the environment and the rights of First Nations, through whose land a pipeline would have to be routed.
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