* Justin Trudeau, son of Pierre, crowned Liberal leader
* Drubbed in 2011 election, Liberals now lead in some polls
* Trudeau campaigns on hope more than substance
* Conservatives say he lacks experience, judgment to lead Canada
By Randall Palmer
OTTAWA, April 14 (Reuters) - Canada’s Liberals crowned charismatic rising political star Justin Trudeau as their party leader on Sunday, relying more on hope and a youthful image than on experience and substance to contest seven years of Conservative rule.
The 41-year-old son of the swashbuckling former Prime Minister Pierre Elliott Trudeau, Justin won a convincing 80 percent of the votes cast by party supporters over the five remaining candidates.
Trudeau had imitated U.S. President Barack Obama in campaigning largely on a message of hope, and he said detailed policy pronouncements will come later, ahead of a federal election due in 2015.
“Canadians want to be led, not ruled. They are tired of the negative and divisive politics of (Prime Minister) Stephen Harper,” he told an Ottawa rally where the results were announced. His wife and young children later joined him on stage.
Within minutes of his victory, the Conservative Party put out a statement seeking to define him as not yet ready to govern.
“Justin Trudeau may have a famous last name, but in a time of global economic uncertainty, he doesn’t have the judgment or experience to be prime minister,” Conservative director of communications Fred DeLorey said.
Trudeau will be the Liberals’ seventh leader in the last decade, including two interim bosses, compared with just two leaders between 1919 and 1958.
That reflects the harder times facing the party, which ran Canada for two-thirds of the 20th century.
In the 2011 election, the Liberals fell to third place for the first time, behind the Conservatives on the right and the New Democrats on the left.
But opinion polls show a Liberal Party led by Trudeau would overtake both the NDP and the Conservatives, amid voter fatigue with the ruling party.
“What Justin Trudeau is benefiting from is probably having the right message at the right time in terms of a swing back to less hyperbole and negativism,” said Nik Nanos of polling firm Nanos Research.
Trudeau, a former teacher who was elected to Parliament in 2008, is 12 years younger than Harper and 17 years younger than Thomas Mulcair, leader of the NDP.
A Nanos survey distributed on Thursday had Trudeau eclipsing Mulcair on most leadership indicators and coming within striking distance of Harper. And a Nanos poll released on Friday had the Liberals ahead of the Conservatives 35.4 percent to 31.3 percent, with the NDP way back at 23.6 percent.
“Today marks the beginning of the end of this Conservative government,” former Liberal Prime Minister Jean Chretien, who won three straight majority governments, declared ahead of the announcement of Trudeau’s election.
In addition to a battle against the Conservatives, Trudeau and NDP leader Thomas Mulcair will fight over who is best placed to claim the votes to the left of the Conservatives.
It was partly thanks to the splitting of the vote on the center and left between their two parties that Harper was able to win three successive elections since 2006.
Mulcair, at the end of his party’s policy convention in Montreal, reiterated on Sunday his rejection of any cooperation with the Liberals in the next election. He noted the Liberals had walked away from a 2008 pact to form a coalition government with the NDP and with the support of the separatist Bloc Quebecois.
“It was the Liberals who went back on their word,” he said. “They’re not reliable.”
Reporters pressed Mulcair repeatedly on how he would try to counter the Liberals under Trudeau.
He said the fact that the Liberals were on their seventh leader in 10 years showed they had “major problems.”
“We’re a government-in-waiting,” Mulcair said. “We’re the only ones who have stood up to Stephen Harper. We’re the only ones who can replace him.”
On Sunday afternoon, in what Mulcair said was an effort to reach beyond the NDP’s base, the party eliminated from its constitution a declaration that progress “can be assured only by the application of democratic socialist principles,” though it gave a nod to the NDP’s “democratic socialist traditions.”
In his acceptance speech, Trudeau focused mostly on generalities, saying the Conservatives did not believe that it was possible to make things better.
“Work hard, stay focused on Canadians. A better Canada is always possible and together we will build it,” he said.
He favors legalization of marijuana and some form of carbon pricing. He opposes the Northern Gateway pipeline to take oil from Alberta to British Columbia, on the grounds that it would cross pristine wilderness, but does not oppose the Keystone XL pipeline to the United States.
He also proposes to change Canada’s electoral system to allow voters to register their second and third choices.