Minnie Mouse, however, need not apply — either as a candidate or as a voter.
Campaign rules announced by the party Thursday appear designed to discourage penny-ante political gadflies and reward candidates with muscular fundraising skills, while simultaneously inviting as many Canadians as possible to cast a ballot next April 14.
"We do think it's taking us to a new level in terms of the amount of participation and the openness of the process," Rae said following three days of fall caucus meetings at a tony resort in western Quebec.
With the once-mighty Big Red Machine down to 35 seats and third-party status in the House of Commons, many Liberals feel the party has to get this leadership race right.
A new class of non-dues-paying "supporters" has been created, a decision made last winter after intense debate at a national policy convention.
Candidates will be able to recruit paying party members or non-paying supporters up to 41 days before decision day.
"Looking at where we are, um, what exactly do we have to lose by trying something new?" said Rae.
Party president Mike Crawley said more than 20,000 supporters are already on board. Some fear the leadership decision could be swamped by casual observers, non-Liberals, political provocateurs or embarrassing aliases.
"I had Minnie Mouse's support in 2006," Rae, a two-time federal leadership contender, quipped in an effort to defuse the issue.
"I have no idea where her vote will go in this particular campaign."
The race rules aim to forestall embarrassments that have dogged recent Liberal leadership races.
"There will be a clear process to authenticate those supporters, to make sure they are individuals and make sure that they are who they say they are," said Crawley.
All ridings will be weighted equally so that areas with large numbers of Liberal party members and supporters, such as downtown Toronto, don't override regions where Liberals are scarce.
"We want to make sure that a candidate can come forward that has support in provinces, such as Alberta, where currently we don't have as many members, perhaps, as in other provinces," said Crawley.
The candidates themselves will have to file monthly expense reports — their accumulated debt can at no point exceed $75,000 — and will also have to file a report as soon as they announce their candidacy showing all expenses incurred back to Thursday, Sept 6.
A $950,000 spending cap is higher than some Liberals had proposed — and almost double the limit set by the NDP in their leadership race last winter — which could favour a high-profile, powerful fundraiser such as Justin Trudeau.
Trudeau continues to play coy, although he did say the rules announced Thursday "look reasonable."
As for his own potential bid, "the deadline seems to be mid-January to announce. I will probably make my intentions clear one way or another before that."
The party has put in place a relatively steep $75,000 non-refundable entry fee, to be paid in three instalments, that could narrow the field of also-rans.
"When you have been an MP for 15 years and you have been a minister and in this party for 30 years, if you want to do it it's not a question of money," said party veteran Denis Coderre. "It's a question of support."
New Brunswick MP Dominic LeBlanc, another prospective leadership candidate, says the next leader needs to commit 10 to 15 years of his or her life "occupied exclusively" with rebuilding the Liberal party and winning elections.
LeBlanc says the leadership race isn't the place for politicians to learn public speaking and he endorses a stiff entry fee.
"The Liberal leadership shouldn't become a kind of practice for the Toastmasters club," said LeBlanc, the son of former governor general Romeo LeBlanc. "I think if you want to practice speech-making there are other places to do it."
The rules are explicitly designed to ensure no candidate limps out of the race with an unpayable debt load.
Montreal MP Marc Garneau's official position on his potential candidacy is that he has not yet made a decision. If he runs, however, he's not going to do it on credit.
"I will not have anything to pay off because I'm not going to put myself in debt," Garneau said. "I will spend the money I have."
Conservative party operatives are still thumping the Liberals at every opportunity — and did so again Thursday — over unpaid leadership debts.
"It is outrageous that nearly six years after their 2006 leadership campaign, four senior Liberals remain in violation of the law for refusing to pay back large loans," Conservative party spokesman Fred Delorey said in an email.
Back in 2006 the Liberals had a refundable entry fee of $50,000 and prospective leaders were allowed to spend up to $3.4 million. New Democrats, by contrast, put a spending cap of $500,000 on the lengthy race that crowned leader Tom Mulcair in March.
The result was a large field of Liberal candidates with little hope of winning, many of whom walked away with huge debts that have been almost impossible to repay. Earlier this summer an Ontario court rejected requests to extend the payback period for three failed candidates, putting their leadership debts into a kind of legal limbo.
MP Hedy Fry and former MPs Martha Hall Findlay and Gerard Kennedy all continue to owe significant sums, as does former cabinet minister Ken Dryden. Several owe the money to themselves, but are not permitted under the rules to simply write off the debt.
Elections Canada appears to be wrestling with how to handle the arrears, since tight donation rules enacted by the Conservative government in January 2007 slashed the lifetime limit that candidates could seek from their donors to $1,000 from a previous limit of $5,400.
Rae, a survivor of two previous federal Liberal leadership races, wouldn't say whether he'd prefer a large, diverse field of candidates or a tight, focused race featuring a handful of bona fide contenders — although the spending rules appear to lean toward the latter.
"There are some (leadership) matches that are one on one, two on two, three on three, and then others where you have lots of different people running," said Rae. "But we're now at the point of transition where this is the necessary focus for the party in terms of where we need to be in 2013."
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