Stephen Harper's Conservatives must target swing voters and vulnerable ridings in urban Ontario and British Columbia if they hope to secure an elusive majority, say pollsters and political scientists watching the campaign unfold.

The Tories controlled nearly half the seats when the recent Parliament was dissolved, as well as almost half the seats in vote-rich Ontario. But they still need to broaden their support among voters if they want to win a majority.

Political pundits say the Conservatives must seize opportunities in Ontario and British Columbia in this election, where more seats are up for grabs than in smaller provinces in eastern Canada.

Andrew Heard, an associate professor in Simon Fraser University's political science department, said the Conservatives will target key seats in these provinces where their candidates finished just behind Liberal and NDP candidates in the last election.

"They finished within five points of the winner in 15 ridings in 2008, most of them in Ontario and B.C., and these seats are the low-lying fruit," Heard told CTV.ca in a recent email.

"This strategy did well for them in the 2008 election, when 11 of their 19 net gains came from seats that had been won by opposition candidates by less than five per cent in 2006."

A Conservative ceiling in the Prairies?

The Prairie provinces remain a major source of Conservative support -- so much so that there are few additional seats that the Tories could take over in this election.

At dissolution, the Tories controlled all but eight seats within the Prairies and Steve Patten, an associate professor in the University of Alberta's political science department, expects that the seat totals won't change all that much in this election.

But Patten said there are a few ridings that will be "interesting" to watch, even if the Conservatives are unlikely to win additional seats.

One of those ridings is Edmonton-Strathcona, which was held by former Conservative candidate Rahim Jaffer for more than 10 years. He lost his seat to NDP candidate Linda Duncan in the last election by a margin of less than 500 votes.

Patten said Duncan snatched the seat from the Tories in 2008 by running a strong campaign and winning support from a group of local Liberals who thought she had a better chance of winning than their own candidate.

In 2011, Patten said "it's going to be close", but he expects Edmonton-Strathcona will hold as an NDP riding. At the moment, the Liberals are intending to have a university student serve as Duncan's competition and the local Tories are currently trying to distance themselves from a campaign volunteer who is under investigation by the RCMP.

The vote was also close in a recent November byelection in Winnipeg North, which was won by Liberal candidate Kevin Lamoureux. But that was a contest in which the Tories placed third and garnered less than 11 per cent of the vote.

"The Conservatives have come second there, but they've never come close," said Patten.

Further east and outside the base

Pollster Nik Nanos says it is "very inefficient" for the Conservatives to carry high margins in the Prairies, when they need more votes elsewhere -- particularly in Ontario.

Speaking with CTV News Channel, Nanos recently said the Conservatives have built a firm base during their five years in government, but they still need broader support.

To do it, Nanos said they need to reach out to the one in five Canadians who are still undecided.

Nelson Wiseman, an associate professor in the department of political science at the University of Toronto, said he also sees room for the Tories to grow in Newfoundland and Quebec, in addition to the opportunities in Ontario and B.C.

There are 75 parliamentary seats assigned to Quebec and the Conservatives controlled only 11 when the election was called.

In his most recent government, Harper has had five Quebec MPs in his cabinet, including Foreign Affairs Minister Lawrence Cannon and Natural Resources Minister Christian Paradis.

On the campaign trail, Harper has signalled his desire to build more Conservative support in Quebec, saying that the Tories "want to see more Quebecers inside our national Conservative government."

In Newfoundland and Labrador, Patten said things are looking better for the Tories with the departure of former premier Danny Williams and his highly effective "Anything But Conservative" campaign that shut out the party during the 2008 election.

The Conservatives could also win votes with Harper's recent pledge to provide federal support to the Lower Churchill hydro project in Labrador, which he said held importance for all of Atlantic Canada.

But when it comes down to it, Patten said the Tories must cast their attention upon the urban ridings of the Greater Toronto Area, Vancouver Island and B.C.'s Lower Mainland where they have more opportunities to pick up a greater number of seats.

"Newfoundland is important, but it's not a lot of seats," he said.

Unforeseen circumstances

While Wiseman said the Conservatives are well-positioned for an election, he points out that there is no guarantee that the party will hold onto the seats they have, as anything can happen in a campaign.

"A lot of it has to do with how the other leaders and the other parties perform," Wiseman told CTV.ca in a recent telephone interview from Toronto.

Wiseman said the overall strategy will be for Harper to run "as flawless a campaign as he can," while dealing with any unexpected curveballs that come his way.

In the early days of the campaign, the Conservative leader has confidently stated that only one of two people will be prime minister after this election has finished: Himself or Liberal Leader Michael Ignatieff. But he has made repeated allusions to the possibility of a coalition government that he has defined as being unstable and a threat to Canada.

Heard said the party will aim to keep Liberals from turning out to the polls, a problem that dogged the Official Opposition in 2008.

"The real danger faced by the Conservatives is not the prospect of their voters switching allegiance, but hundreds of thousands of Liberals flocking back to the polls," Heard said via email.

"The Conservatives could lose a good number of their seats if that were to happen."

If the Conservatives fail to win a majority again, Wiseman expects that Harper will remain Tory leader because he is well-regarded within the party and has no internal challengers for his job.

"They are in total awe of him," said Wiseman.