The results of the party's leadership race will be announced Sunday in Ottawa, a contest Trudeau is widely believed to have all but locked up. Recent polls have suggested the Liberals are climbing their way back into contention, with the help of Trudeau's high-profile candidacy.
The prospect, however, that the man with the famous family roots could be chosen Liberal leader — and eventually, perhaps, prime minister — was met this week with mixed reaction in his Papineau riding.
For Trudeau, political victories in his home riding have always been anything but a sure thing.
The largely lower-middle-class urban area, north of downtown, includes a contingent of voters who have historically supported the pro-independence Bloc Quebecois.
Trudeau first won the seat from the Bloc in a tight 2008 race, a margin of victory he widened three years later.
A bedrock of his support is centred in the neighbourhoods that are home to Papineau's big immigrant communities.
"He's our man," said King Kwateng, owner of Produits de Beaute Mama Africaine, a store in the Parc Extension district that specializes in hair products and wigs.
"The first time I saw this guy on television, I said, 'This guy is a future prime minister of Canada.' "
That moment came, Kwateng said, in 2000 when Trudeau delivered the eulogy at the state funeral for his father, former prime minister Pierre Elliott Trudeau.
Perched on a shelf in Kwateng's cramped office at the back of his store are two framed photos of Justin Trudeau and a greeting card featuring a picture of the MP's family.
The framed photos show Trudeau attending a local Ghanaian celebration at a park a few years ago.
The people in Papineau link Trudeau's popularity here to his visibility, charisma and knack for connecting with locals.
Inside a nearby coffee shop, George Georgiou estimates that 90 per cent of the area's Greek population backs Trudeau, himself included.
Georgiou, who moved to Parc Extension from Greece more than 40 years go, said people here like Trudeau because of his energy and his bloodline.
"I would say among the immigrants like us ... Trudeau is very popular," said Georgiou, who used to carry around a photo of Pierre Elliott Trudeau in his jacket pocket.
But he predicts that same lineage to be a major obstacle for his MP across Quebec, and in the riding, during any Trudeau bid for the prime ministership in the 2015 election.
Further east in Papineau, Pierre Elliott Trudeau's legacy during constitutional battles is still deeply unpopular among some voters.
Many in the riding's Villeray neighbourhood remain skeptical of his 41-year-old son's abilities and shudder at the thought of another Trudeau eventually becoming prime minister.
"I hope it doesn't happen," said Christiane Vogel, as she walked near Trudeau's riding office.
"I don't support Justin Trudeau at all. I don't think he has enough experience, he's not ready to do it."
Vogel, who doubts Trudeau could do or say anything to win her vote, said his discourse lacks depth.
She added that many of her neighbours — in an area she considers Bloc-friendly — associate him with his father, a man they believe failed to do what was right for the Quebec nation.
Another Villeray woman let out a derisive laugh when she was asked about the possibility Trudeau could become Liberal leader.
"My mother always told me that it's better to be nice with our words and I don't have a lot of positive things to say," the woman said as she walked into a pharmacy next door to the MP's office.
At just nine square kilometres in size, Papineau covers the smallest area of any electoral district in Canada.
But the riding, which includes part of Pierre Elliott Trudeau's old Mount Royal constituency, has been ground zero for big electoral fights in recent years.
Trudeau defeated popular Bloc incumbent Vivian Barbot in 2008 by fewer than 1,200 votes. He captured less than 42 per cent of the total ballots versus nearly 39 per cent for Barbot.
The win reclaimed the riding for the Liberals, who had held Papineau for decades before losing it to Barbot in 2006.
In 2011, Trudeau increased his margin of victory to more than 4,300 ballots when he beat New Democrat runner-up Marcos Radhames Tejada. Barbot finished a close third in an election that saw the Liberals reduced to third-party status.
"It should have been one of the first ridings to drop to the orange wave," Trudeau said during a recent appearance at McGill University about holding off the NDP's 2011 surge in Quebec.
"Instead, I tripled my margin of victory."
The NDP was asked by The Canadian Press for an interview with Tejada or someone in Papineau who could discuss Trudeau's riding work. But the party did not provide anyone for comment.
A spokesman for the Bloc, meanwhile, said his party was rebuilding in Papineau and could not line someone up from the area to talk about Trudeau. He said Barbot had retired and could not be reached for comment.
Another political accomplishment Trudeau has reminded his audiences about was his hard-fought feat of securing the Papineau Liberal nomination in 2007 over strong candidates from the community.
"I didn't get any help from the backrooms of the party because they actually weren't sure that they wanted me," Trudeau told students during the McGill visit in February.
"Therefore, I had to work and build an organization on the ground that was strong enough to not just win the nomination against two very well-respected local Liberals, but then take back a very difficult seat from the Bloc Quebecois and one of the star Bloc Quebecois MPs."
Longtime municipal politician Mary Deros was Trudeau's runner-up in that nomination contest.
The Parc Extension councillor said in an interview she's been working with Trudeau ever since to build local interest in the party.
"I'm very happy that he won because I know he has great potential," said Deros, who helped introduce Trudeau at the October event where he announced his candidacy for the Liberal leadership.
"You see the difference from (his) first day as MP to today. Five years later, he's very assured, he's going for the leadership of Canada and he's very confident."
She said his team in the riding will face the challenges of picking up the slack if his responsibilities grow in Ottawa.
"We will have to share him with the rest of Canada, that is very obvious," she said.
"But we will be proud to say that we are his roots in federal politics."
The co-ordinator of a umbrella group for community organizations in Villeray credited Trudeau for being available to the people of Papineau despite a busy schedule.
Andres Fontecilla, who heads the Conseil communautaire Solidarites Villeray, ran provincially in the area last year for the small, pro-independence party Quebec solidaire.
He said many people here cast votes based on the candidate's track record, even if it clashes with their personal beliefs on the constitutional question.
"Mr. Trudeau is very, very attentive (and) when he can consult us, give us a hand, he is always present,'' said Fontecilla, whose organization represents groups from different sectors, including those that address local poverty.
"It's not an automatic Liberal riding. You have to fight to have these ridings and I think this is something that people appreciate (about Trudeau).
"(Barbot) was very popular, it wasn't easy for Mr. Justin Trudeau."
Fontecilla thinks Trudeau's constituents would likely see less of him if he were chosen Liberal leader. But he expects it would be "excellent news" for the people of Papineau if their MP eventually became prime minister.
"He would have access to levers that could help the population he represents," he said.
"I think that Mr. Trudeau has all the capacities to fill this post."
Back in Parc Extension, Kwateng boasts that he advised Trudeau in 2008 to never forget the people who elected him, even if his responsibilities eventually expanded elsewhere in the country.
"He's the people's man because he always comes around (to) talk to the people in the riding," Kwateng said.
"So, I think if he becomes prime minister he will have time to visit us."