More Canadians would consider voting for the New Democrats or the Liberals than the governing Conservatives according to a new poll, but too few support either one to drop the Tories to second place.

An online poll by Nanos Research for the CBC shows 45 per cent of Canadians would consider voting for the Conservative Party, compared to 49 per cent who said they would consider voting Liberal and 51 per cent who might cast their ballot for the New Democrats. As ceilings go, these numbers are all more than enough to win a majority government in our electoral system.

But the Conservatives are doing the best job of corralling their supporters. Current polls put the party around 35 per cent, suggesting about 78 per cent of Canadians who would consider voting Conservative are already giving them their support. The New Democrats currently have the support of only 57 per cent of those who might vote for them, while the Liberals have less than half.

The Conservatives did even better in getting their base out in the last federal election, as they received 40 per cent of ballots cast, or almost nine out of every 10 Canadians who say they would consider voting Conservative. The New Democrats got six out of every 10 of their potential supporters to the polls, while the Liberals managed to convince less than four out of every 10 of their sympathizers.

But the Tories may be scraping the bottom of the barrel, as the poll suggests the party has no further room for growth in British Columbia or the Prairies. That means Stephen Harper will need to look to central and eastern Canada for new voters, particularly considering that the New Democrats appear to have made gains west of Ontario.

However, the poll indicates Tories just don’t have much room for improvement. While 50 per cent of Ontarians said they would consider voting Conservative, that is hardly more than the 44 per cent who did in 2011. And 42 per cent, the number of Atlantic Canadians who said they would consider voting Tory, is not much more than the 38 per cent of votes the Conservatives gathered in the region in the last election.

That leaves Quebec, where 37 per cent of voters said they would consider casting their ballot for the Tories. Though that is much greater than the 17 per cent the Conservatives actually got in the province, polls suggest the Tories have been losing support in Quebec -- not winning it.

There is plenty of room for growth for the NDP and Liberals in every part of the country. A majority of voters in Ontario, Quebec, and Atlantic Canada said they would consider voting for one party or the other, while more than 45 per cent of British Columbians said the same. The two parties have lower ceilings in the Prairies -- 37 per cent for the Liberals and 43 per cent for the NDP -- but that is a far greater share than either party obtained in any recent election.

The Conservatives have almost sole claim over the 45 per cent of Canadians who consider them worthy of their vote. By contrast, the two main opposition parties have so far been unable to win over much more than half of their pool of voters.

As long as this remains the case, the Conservatives will keep winning.

Éric Grenier taps The Pulse of federal and regional politics for Huffington Post Canada readers on most Tuesdays and Fridays. Grenier is the author of ThreeHundredEight.com, covering Canadian politics, polls and electoral projections.

Related on HuffPost:

Loading Slideshow...
  • <a href="http://www.huffingtonpost.ca/2013/01/23/toyota-lexus-cambridge_n_2534019.html">Ontario Premier Dalton McGuinty and Prime Minister Stephen Harper shake hands after attaching the final parts to a Lexus SUV</a> at the Toyota automotive plant in Cambridge, Ontario on Jan. 23, 2013.

  • Prime Minister Stephen Harper speaks with French President Francois Hollande On Jan.16, 2013. <a href="http://www.huffingtonpost.ca/2013/01/14/canadian-mission-mali-france-cargo-plane_n_2472597.html">Canada is contributing one of its large C-17 military cargo planes to deliver supplies to the capital of Mali after a request from France</a>. <em>With files from The Canadian Press</em>

  • <a href="http://www.huffingtonpost.ca/2013/01/16/stephen-harper-meets-with_n_2491152.html">Prime Minister Stephen Harper meets with the winners of the Quebec reality show 'Occupation Double'</a> on Jan. 16, 2013.

  • Prime Minister Stephen Harper takes part in a photo opportunity with Minister of State for Small Business and Tourism Maxime Bernier and entrepreneurs at CBC headquarters Jan.14, 2013 in Montreal.

  • Prime Minister Stephen Harper listens to a question during a news conference, Monday, January 14, 2013 in Montreal.

  • <a href="http://www.huffingtonpost.ca/2013/01/12/stephen-harper-david-chen-community-service-medal_n_2464256.html">Shopkeeper David Chen (centre) stands with Prime Minister Stephen Harper and Ontario's Lieutenant Governor David Onley after receiving his Diamond Jubilee Medal</a> for outstanding service to his country in Toronto on Jan. 12, 2013. Chen is a Toronto grocer who was charged in 2009 but later acquitted for chasing down and detaining a shoplifter.

  • <a href="http://www.huffingtonpost.ca/2013/01/11/harper-first-nations-meeting_n_2459305.html">Prime Minister Stephen Harper meets with First Nations leaders</a> in Ottawa on Jan. 11, 2013.

  • <a href="http://www.huffingtonpost.ca/2013/01/08/harper-thomas-boni-yayi_n_2433191.html">Prime Minister Stephen Harper greets the President of the Republic of Benin Thomas Boni Yayi</a> in Ottawa on Jan. 8, 2013.

  • Prime Minister Stephen Harper hangs a photo of his mother, Margaret, on the 'Nonna Wall' at Ritorno Restaurant in Oakville on Jan. 4, 2013.

  • Canadian Prime Minister Stephen Harper is reflected in the glass door of an electrical panel as he speaks at Ford Motor plant in Oakville, Ontario on Jan. 4, 2013. <a href="http://www.huffingtonpost.ca/2013/01/04/automotive-innovation-fund-canada_n_2410319.html">Harper announced renewal of the Automotive Innovation Fund</a>.