Those lending their names to the "tribute committee" include a who's who of current and former Canadian politicians of all partisan stripes.
They include former Conservative prime minister Joe Clark, former NDP leader Ed Broadbent and a host of one-time Conservative, Liberal and NDP premiers: Jean Charest, Mike Harris, Bill Davis, Gary Filmon, Roy Romanow, Brian Tobin and Bernard Lord.
Even Stephen Harper, widely perceived to be among the most ruthless of partisans, is involved. The current Conservative prime minister is to honour the former Liberal prime minister via video at the gala dinner Tuesday in Toronto.
But perhaps most surprisingly, Chretien's erstwhile leadership rivals, former prime ministers John Turner and Paul Martin, have also signed on to promote the event, to which more than 700 people have bought tickets at $400 a pop.
"I thought it was a very strong signal that they both would agree" to help honour Chretien's 50 years of public service, said Ed Lumley, a former Pierre Trudeau and Turner-era cabinet minister who sought Martin's endorsement.
"I think it's a very strong sign that the party is (acknowledging) that the past is the past."
Lumley said Martin, whose bitter leadership feud with Chretien capped almost four decades of factional infighting that nearly destroyed the party, "didn't hesitate for moment" when asked to join the tribute committee. Nor did Turner.
With Justin Trudeau and a new generation of Liberals breathing new life into a party left for dead in the 2011 election, Lumley believes Martin and Turner both appreciate that it's time to bury the hatchet, once and for all.
"The fact is, we all want to do our best for Mr. Trudeau," Lumley said in an interview.
"He doesn't need to inherit the problems of the past. So the onus, I think, is on all of us to put aside whatever differences we have."
Trudeau is one of numerous luminaries scheduled to speak at the tribute but organizers stress it is not a partisan Liberal event. Indeed, they say it's about honouring someone who has devoted 50 of his 80 years to public service and about reminding scornful Canadians that politics can be a noble calling.
"It's a way to recognize an exceptional Canadian," said Kip Daechsel, a Toronto lawyer and longtime Liberal who has helped organize the event.
"And also to say to people, and hopefully there'll be a lot of young people there, that public service in politics is still an honourable thing and you can make a difference and it's something that should be looked at positively and not just negatively."
In the United States, former presidents are routinely honoured by their successors, Lumley noted, their contributions to public life celebrated.
That rarely happens in Canada. One recent exception was Harper's invitation to former prime ministers to accompany him on a flight to South Africa for Nelson Mandela's funeral last month.
"It's about time ... I think there should be more of that," said Lumley.
Chretien was first elected in 1963 and remained active in politics for the next 40 years, with only a brief hiatus from elected office in the mid-1980s, after he lost his first leadership bid to Turner. He served in almost every senior ministerial position in Pierre Trudeau's cabinet, including finance and justice.
He was Trudeau's go-to minister during the 1980 referendum on Quebec independence and spearheaded his subsequent effort to patriate the Constitution with a charter of rights.
Chretien assumed the helm of the Liberal party in 1990 and led it to three back-to-back majority victories — a feat exceeded by only one other prime minister, Sir Wilfrid Laurier — before retiring in 2003, amid the sponsorship scandal and rancour over Martin's leadership aspirations.
Since then, he's continue giving private advice to subsequent Liberal leaders while resuming a law practice. In 2012, Chretien was appointed by Harper as Canada's representative to the Diamond Jubilee Trust, a Commonwealth initiative to raise money for charities in honour of Queen Elizabeth's 60 years on the throne.
"You can disagree with him ... but the fact is he's done it for the people of Canada and I think that's what resonates," said Lumley.
Proceeds from the event are being donated to La Maison de la francophonie de Toronto, an umbrella group that supports non-profit francophone support groups.
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