Calgary byelections less about who wins, more about how much they win by

Calgarians will go to the polls in two federal byelections Monday, and while there's little doubt about who will win, the margins of victory will be closely watched by all sides.

Analysts expect the Conservatives will hold on to the seats vacated by Stephen Harper in Calgary Heritage and Jason Kenney in Calgary Midnapore.

But candidates are nevertheless fighting hard for every vote, knowing a strong showing can set them on a path toward future victories.

Parties that gain vote share in a byelection usually go on to gain support provincewide in the next general election, according to an analysis by CBC's poll analyst Éric Grenier.

• ANALYSIS | Byelection performance can be predictive of future results

Scott Forsyth, the Liberal candidate in Calgary Heritage, is well aware of that.

He's been knocking on residents' doors for weeks, hoping against the odds to win on Monday, but also playing the long game.

"We really want to build on each successive election," Forsyth said.

"So I'm hoping very much we can improve upon even the great strides that were made in the last national election here in Calgary Heritage, and we're going to just keep on building our support and outreach right up until the next election in 2019. So this is laying a foundation that's going to be a part of our future."

The Liberals earned 26 per cent of the vote in the southwest riding in 2015, up from just seven per cent in 2011, and they're aiming to beat that on Monday.

Meanwhile, on the other side of Macleod Trail, Conservative candidate Stephanie Kusie has also been campaigning hard.

She's an overwhelming favourite in the riding of Calgary Midnapore, but she's not willing to coast to victory.

"I never take anything for granted," Kusie said.

"I think that you have to work very hard, meet the electorate, have them understand that you are out there working hard for them."

She, too, has spent weeks leading up to Monday's vote by reaching out to voters on their doorsteps, over the phone and through social media.

Turnout in byelections is typically lower than in general elections, which can make get-out-the-vote efforts all the more important for parties looking to maximize their share of the ballots.

But it would be a "real surprise" to see either riding go to anyone but the Conservatives, said Lori Williams, a professor of policy studies at Mount Royal University,

"They are truly Conservative strongholds. There are a lot of people there that have a lot of faith and loyalty to Stephen Harper and to Jason Kenney," she said.

"The best the Liberals can hope for is that they shrink the margins, that they show themselves to be a credible force in Calgary and I think, again, they're looking longer term."

Aside from the Conservatives and Liberals, no other candidates in Calgary Heritage or Calgary Midnapore earned a double-digit share of the vote in the 2015 election.

Liberal Haley Brown picked up 23 per cent of the vote running against Kenney last time around, and she's running again against Kusie in the byelection.

Also running are NDP candidate Holly Heffernan, Green Party candidate Ryan Zedic, Larry Heather with the Christian Heritage Party of Canada and Kulbir Singh Chawla with the National Advancement Party of Canada.

• ANALYSIS | Midterm byelections to test Liberal government and leaderless opposition parties

Calgary Heritage Conservative candidate Bob Benzen didn't respond to a request for an interview.

In addition to Forsyth, he's up against five other challengers, including:

• Khalis Ahmed, NDP.
• Stephen J. Garvey, National Advancement Party of Canada.
• Darcy Gerow, Libertarian Party of Canada.
• Taryn Knorren, Green Party of Canada.
• Jeff Willerton, Christian Heritage Party of Canada.

The polls are open in both Calgary ridings from 7:30 a.m. to 7:30 p.m. MT.

Information on where to vote is available here from Elections Canada.

Byelections are also being held Monday the Ontario ridings of Markham–Thornhill and Ottawa–Vanier and in Saint-Laurent in Quebec.