As the Liberal fortress fell in Toronto, one of the breaches was in the west end riding of Parkdale-High Park, where Liberal incumbent Gerard Kennedy had managed before to buck the national trend.
He won in the 2008 election, despite a disastrous national campaign by then Liberal leader Stéphane Dion.
This time, however, challenger Peggy Nash, who was the local MP from 2006 to 2008, won back the riding by more than 6,000 votes.
"This campaign has been about change and the credit is due to NDP Leader Jack Layton," Ms. Nash told her jubilant supporters shoehorned into a Queen Street West bar as they started chanting "Jack! Jack! 'stache! 'stache!"
She told reporters that she had been concerned because she had been defeated by Mr. Kennedy before. But, she said, "One of the reasons I got into politics was because the Liberals were taking Toronto for granted."
Around her, lifelong NDP workers were stunned by the scope of their party's wave.
"I had to wait until I had grey hair to see this," said Steven Gurevitch, 56, who first volunteered for the party as a teen. "I'm totally amazed."
The Conservatives were never a factor in this diverse downtown riding where the electoral dynamic was often described as a fight between the left and the "more left."
Instead, Ms. Nash and Mr. Kennedy, two prominent candidates, community-oriented and progressive-minded, faced off in a contest where they both emphasized their commitment to public transit, funding to municipalities and helping the poor and the disabled.
Provincially, the area is an NDP stronghold, but at the federal level it was only five years ago that Ms. Nash made a breakthrough for her party. However, two years later, Mr. Kennedy took the seat in 2008 by 3,000 votes.
The campaign had its testy moments. Ms. Nash said she would be more involved than her rival as she criticized Mr. Kennedy's parliamentary attendance record.
Mr. Kennedy, portraying himself as a positive campaigner who stayed above attack politics, complained that the NDP campaign was "deceitful" in failing to explain that, while away from the Commons to attend environmental events, he paired his vote with other MPs to neutralize his absence.
The bad blood continued on voting day, when supporters on both sides made allegations that bogus phone messages misled voters about their polling stations' location. (Elections Canada spokeswoman Francine Bastien couldn't confirm the allegations. "Those reports are anecdotal, we do not have official figures," she said.)
A former Ontario education minister and former food bank director, Mr. Kennedy had become one of the big names of the Liberal caucus after entering the party leadership race in 2006.
Ms. Nash, a negotiator for the Canadian Auto Workers, also kept a high national profile as president of the NDP.