OTTAWA -- The popularity of the federal Conservative government will be put to the test next month in byelections in three provinces.

Prime Minister Stephen Harper called for votes November 26 to fill vacancies in the Commons for Victoria, Calgary Centre, and Durham - the riding just east of Toronto vacated by embattled former cabinet minister Bev Oda.

"Our candidates will be contrasting the strong economic record of Prime Minister Stephen Harper with the dangerous economic policies of Thomas Mulcair," said Conservative Party spokesman Fred DeLorey in a statement Sunday.

NDP leader Thomas Mulcair says his party is ready to fight in all three ridings, including Calgary where the New Democrats would be lucky to scrape together 15% of the vote.

"I don't concede anything to an adversary ever," said Mulcair. "Our team is going to fight hard in all three."

All three ridings lack an MP for different reasons.

While Durham was opened up by Oda's retirement from politics, Calgary Centre became vacant when long-time Tory MP Lee Richardson left to work for Alberta Premier Alison Redford.

NDP MP Denise Savoie resigned from her Victoria riding in August for health reasons.

Victoria has a full slate already, including New Democrat Murray Rankin, who sees Tory Dale Gann as his main rival.

"I think it is the Conservative Party that we're up against," said Rankin. "The Liberal Party is the third party in Canada. It's the third party in my riding."

Conservative and Liberal candidates are already knocking on doors in Durham and Calgary Centre too, but the New Democrats have yet to name their flag bearer in those ridings.