Liberal superstar Adam Vaughan defeated New Democrat hopeful Joe Cressy in Trinity-Spadina, long a New Democrat riding once held by Olivia Chow, widow of beloved former NDP leader Jack Layton.
Further east in Scarborough-Agincourt, Arnold Chan, a lawyer and former political aide at the Ontario legislature, managed to keep the riding in the Liberal fold, beating elementary school teacher and Conservative candidate Trevor Ellis.
And in the northern Alberta riding of Fort McMurray-Athabasca, ground zero in the oilsands debate, Liberal Kyle Harrietha had some 34 per cent of the vote even as he went down to defeat at the hands of Tory candidate David Yurdiga.
"The results of these byelections have proven that our message is reaching and engaging Canadians," Trudeau said in a statement.
"Liberals' results and significant gains make clear that Albertans in particular will not be taken for granted. Voters have shown us that they believe that every Canadian deserves a real and fair chance at success."
Only in the southern Alberta riding of Macleod were the Liberals not a factor: former journalist John Barlow cruised to victory with about 69 per cent of the vote, well clear of Liberal rival Dustin Fuller.
Barlow wasted little time before declaring victory Monday.
"This is the culmination of eight months of hard work and it definitely feels worthwhile today. I thought this day would never come," Barlow said in a victory speech that came just 30 minutes after the polls closed.
More than 100 supporters cheered loudly when he entered the Italian restaurant in High River accompanied by his wife Louise and children.
"What this really came down to was passion and how hard we worked. The message we had is Macleod is not going to be forgotten. We cannot take Macleod for granted."
Barlow said he intends to locate his constituency office in High River, which has been decimated since massive floods last year turned the town's streets into rivers of water.
"If there's one issue that really bound Macleod together over the past year was that flood," he said.
"We have a lot of work to do and I will be here from this day forward to make sure that work gets done."
Scarborough-Agincourt had long been the personal fiefdom of Jim Karygiannis, a bare-knuckle political brawler who held the riding for the Grits for 25 years.
His decision to retire from federal politics to run municipally gave the Conservatives an opportunity to paint another suburban Toronto riding blue, appealing to the conservative, family values of the ethnically diverse population.
But despite papering the riding with flyers attacking Trudeau's support for legalization of marijuana, Conservatives didn't make much of a dent in Liberal support. Chan actually managed to increase the Liberal margin of victory.
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