NDP's Quebec support built around Layton
When Jack Layton travelled Quebec during the 2011 election campaign, it was in a bus plastered with a picture of his face so big it dwarfed his real height.
The NDP leader was the key to the party's surprising victory in the province on Election Day. Pollsters had noted the NDP's numbers were just catching up with Layton's personal popularity numbers, which had always been much stronger than the party's.
And the NDP's widely acknowledged breakthrough moments in the province came when the likeable leader appeared on TV - on the popular French-language show Tout le monde en parle, and on the French-language leaders' debate.
He was the force that pulled voters to the NDP after years with the Bloc Québécois and Liberals.
"They fell for his positive side," Marie Grégoire, a former Quebec provincial politician, told CBC News the day after the election. "You know, like, 'yes, I smile.' And I think people liked it."
That same day, Layton defended his MPs from questions about their lack of political experience. Three were McGill University students and another was the youngest-ever MP at 19 years old.
"We will have a lot of new blood, new energy, new talent ... when people vote for change, that's what they're hoping happens," Layton said.
"Young people got involved in this election in an unprecedented way.... We should see that as something to celebrate, not something to criticize."
More than half the NDP's MPs came from la belle province - 59 out of 103. Only two had sat in the House of Commons before, including one who sat as a Liberal. Montreal MP Thomas Mulcair, the party's deputy leader, had only won the party its first Quebec seat in a September 2007 by-election.
In an election where a handful of MPs were elected without campaigning, it's clear that some support was for Layton or the party more than the local candidate.
Now, the party has to deal with rebranding itself as a team instead of as a leader.
Supporters have said Layton's work in building a party organization, tracking supporters and donors, and generally modernizing its systems would continue after his leadership had ended.
The party has four full years before the next election campaign. Some MPs look like promising future leaders - but nobody expected to have to find a new one so soon.
Whoever takes over will have to be proficient in French so he or she can communicate with Francophone supporters and try to hang on to those Quebec seats. Many of the obvious leadership contenders aren't bilingual.
They'll also have to bridge the gap between union workers, urbanites and activists if they want to maintain broad support.
But it will be hard to find anyone as likeable as Layton, who was known to most simply as "Jack."