OTTAWA — The Liberal leadership deck is getting crowded.

It's also starting to list heavily to the left. By the end of next week, 10 contenders will have formally declared their candidacies, including Bob Rae, Gerard Kennedy and Ken Dryden.

Most of them openly advocate shifting the party to the left in hopes of recapturing votes that moved to the New Democratic Party in last winter's election. The shift was enough to cost the Liberals the election and produce a minority Conservative government.

Rae, a one-time NDP premier of Ontario, has paved the way for his leadership bid by calling for a united front among all "progressive" Canadians to block Stephen Harper's Tories from winning a majority next time.

Rae is expected to formally throw his hat in the ring next Monday.

The Liberal party has governed for all but 30 of the last 106 years, in large part due to its unerring ability to monopolize the political middle ground.

But with Harper's Tories now attempting to usurp the centre and the NDP targeting the Liberals' left flank, Canada's self-styled natural governing party is struggling to reposition and differentiate itself from its rivals.

Of the 10 leadership candidates expected in the race by next week, only one - Toronto MP and former minister Maurizio Bevilacqua - is intending to run on an unabashedly centre-right, pro-business agenda. He will formally launch his campaign Wednesday, focusing heavily on the need for improved productivity and economic growth.

Joe Volpe, another Toronto MP and former minister, will launch his campaign towards the end of the week. He's billing himself as the candidate best able to reach out to Canada's multicultural communities.

Scott Brison, a youthful, openly gay Nova Scotia MP and former Tory defector, is poised to formally join the race on the weekend. He will cast himself as a representative of the new, progressive generation of Liberals.

Toronto MP Carolyn Bennett, presenting herself as a champion of democratic reform, is expected to formally launch her bid early next week, as is Kennedy.

Kennedy quit his job as Ontario's education minister earlier this month to clear the way for a leadership run. A social activist who founded food banks in Edmonton and Toronto, Kennedy is being touted as someone who can lure NDP voters back into the Liberal fold.

Dryden, the past hockey great, will also formally join the race later next week. As the minister who finally delivered on the Liberals' decade-old promise to create a national child care program, Dryden is another contender touted for his ability to woo left-wing voters.

At least two of the three candidates who've already formally joined the race are also running hard from the left.

Renowned scholar and rookie Toronto MP Michael Ignatieff launched his leadership bid earlier this month, urging the party to stake its ground firmly on the "centre-left" of the political spectrum.

And former minister Stephane Dion, who formally launched his campaign the same day as Ignatieff, is running as the champion of environmental sustainability.

Toronto lawyer Martha Hall Findlay has also declared her candidacy, casting herself as a fresh face who can heal the wounds left from years of leadership feuding between Paul Martin and his predecessor Jean Chretien.

Liberals will choose a successor to Martin at a convention in December.