OTTAWA --- New Democratic Party leader Thomas Mulcair announced Thursday the appointment of three deputy leaders and named B.C. New Democratic Party MP Nathan Cullen, who surprised the political world with a strong third-place finish in last month's leadership race, as his House leader.

Mulcair's first caucus shuffle since winning the party's leadership last month involved a delicate balancing act, as he had to reward supporters, bring in leadership rivals, and balance regional interests.

Moments after his victory Mulcair named Libby Davies, the veteran Vancouver East MP, as his deputy leader - a position she served under the late Jack Layton and interim leader Nycole Turmel.

The two new deputies are Halifax MP Megan Leslie, who remains environment critic, and Ontario MP Dave Christopherson. Leslie was neutral in the leadership race, Christopherson backed Mulcair, and Davies supported second-place finisher Brian Topp.

Cullen, who was first elected in the Skeena-Bulkley Valley riding in 2004, replaces Ontario MP Joe Comartin as House leader.

"Nathan has shown a great capacity to involve people in the political process. His persuasiveness, his innovative thinking and his respect for others are his hallmarks," Mulcair said in a statement.

"Nathan shone as a great debater and I am thrilled he agreed to serve as our House Leader."

Turmel will retain a senior role as party whip. Quebec MP Francoise Boivin was promoted as justice critic, leadership candidate Paul Dewar kept his post as foreign affairs critic, and fellow candidate Peggy Nash got her old job back as finance critic.

Alberta's only New Democrat MP, Linda Duncan, moved from aboriginal affairs to critic for the Public Works and Government Services department.

B.C. MP Peter Julian, who filled in for Nash as finance critic, becomes responsible for energy and natural resources. Another B.C. MP, Jinny Sims, takes over as immigration critic while fellow British Columbian Don Davies moves from immigration to international trade.

Cullen's candidacy wasn't taken seriously by pundits and media insiders when he first announced his intentions last autumn, but he built up a considerable following due to strong debate performances and to his appeal for greater Liberal-NDP cooperation to defeat Prime Minister Stephen Harper.

He placed third on the first ballot behind Mulcair, who had the strongest support among the party's MPs, and Topp, the choice of key party establishment figures and veteran organizers.

On the final ballot Cullen remained in the third spot, with 25 per cent of the votes.

Many expected him to finish behind candidates Nash and Dewar.

While Mulcair and the other candidates rejected Cullen's call for opposition parties to field a single candidate in Tory-held ridings, the new leader was faced with a dilemma on how to reward Cullen's populist campaign.

The challenge was heightened given the prominent role already given to Davies, a prominent figure among the party's more left-leaning members.

Her appointment was viewed as an important symbolic measure to ease concerns among party members that Mulcair, a former member of Quebec Liberal Premier Jean Charest's cabinet, would move the NDP too far to the centre.

But Mulcair also had to give a prominent role to Cullen, despite concerns that the West Coast might be over-represented in the party's upper echelon.

"Nathan is important to Mulcair and the party for several reasons. He's young, telegenic, and ran a brave, disciplined, positive campaign," said Marcella Munro, a Vancouver-based lobbyist, NDP strategist and political commentator.

"He deserved to be rewarded. But probably most important is that Cullen is from a northern, rural riding in B.C., and he took out a Conservative when he was elected in 2004.

"Cullen is someone that represents what the NDP needs to do to form a government — hold on in Quebec, and figure out how to beat Conservatives in ridings where the NDP is the second choice. It's a critical part of the path to 24 Sussex for us, and a strong signal that Mulcair gets how critical the West will be to our continued electoral success."

Cullen, the father of twin toddlers, did not take on a critic role after the May 2 election at his request.

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