He's quick to laugh - at himself more often than at others. Even his detractors call him Smiling Jack.
He is more than a fair musician. Not only does he play guitar, he surprised journalists this week with an impromptu rendition of Hit the Road Jack on a grand piano in the lobby of a hotel in Saint John, N.B.
He is an experienced politician - the leader of what was the fourth party in the House of Commons who sometimes had trouble being heard.
But, with the NDP on track to make unprecedented electoral gains, it is time to ask what Canadians have really learned about Jack Layton.
1. He is resilient.
Mr. Layton gripped a crutch as he hobbled to his tour bus on the first day of the campaign. Less than a month earlier, he was in the hospital having hip surgery to repair a hairline fracture. But electioneering appeared to energize him. Every day he walked a little faster. And on Monday he leapt into the air to see above a crowd.
He is also a political survivor. Elected to lead the federal New Democrats in 2003, Mr. Layton is on his fourth election campaign. And his party has seen its section of the House of Commons increase with each vote.
2. He controls his message.
Whether it is in speeches, interviews or taking questions from the media, Mr. Layton does not stray from his rehearsed lines.
He will appear at the back of a campaign plane for a singalong with reporters, but he does not speak off script.
Conservative Leader Stephen Harper is accused of restricting access to the public and the media. Liberal Leader Michael Ignatieff began his federal political career by planting his foot in his mouth more than once and is still prone to saying things that can be used against him.
By contrast, Mr. Layton allows Canadians to get close - even those with pens and cameras. But the political experience gained over nearly three decades of public life has created a skilled performer who rarely makes an impromptu remark unless it is an innocuous, often funny, quip.
3. He smiles through his contradictions.
When the Liberals proposed a carbon tax in 2008, Mr. Layton said it was "wrong" and "won't work." When he proposed a cap-and-trade system in his own party's 2011 platform that would siphon billions from carbon emitters, he refused to label it a carbon tax.
Mr. Layton said this week that he could not support strategic voting for the Liberals, even in cases where vote splitting on the left could turn seats over to the Conservatives. Yet, he has told Liberal-leaning voters in Western Canada that the only way to defeat the Conservatives is to vote NDP.
When he was British Columbia and Ontario, he derided the harmonized sales tax. But when he was in Nova Scotia, he praised the NDP government in that province that raised the HST by 2 per cent for its innovation in making the tax more fair.
4. He is his own brand.
It is a brand that Mr. Layton himself established and one that he has not allowed his rivals to redefine.
It is his head that is pasted on the side of the tour bus and his name that is affixed to the side of the plane.
When New Democrat officials said this campaign would be run at a slower pace than those of previous elections, they explained that Canadians already know their Leader. Mr. Layton, they said, does not need to make three or four stops a day just to introduce himself to the electorate.
In 2004, it was just the opposite. But the NDP campaign was still structured around the leader with signs that read: You Don't Know Jack.
His defining moment
On April 14 in Montreal, Mr. Layton spent the night with reporters and his entourage at a bar attached to the city's Bell Centre watching the Montreal Canadiens in a playoff game. The picture of his cheer when the team scored a goal spread across Quebec like a tipped can of orange paint.
That followed his successful appearance on the hit show Tout le monde en parle, and his successful performances in both the English- and French-language debates. The following day, his poll numbers began to rise in Quebec, and have yet to come down.