Although many look at opinion polls to forecast what candidate will likely win on Oct. 19, the ability of the parties to get their supporters out come election day could well be the deciding factor in a tight race.

"Five per cent difference in polling means nothing on election day if you can't get your vote out the door, or the other guy does it better," said Bill Tieleman, a communications consultant and former NDP strategist.

"You can overcome fairly significant margins if you have the ability. If you get 50 per cent [turnout] and the other guy gets 33 per cent, then it doesn't matter if you're down [in the polls]."

Conservative strategist Jason Lietaer agreed, stressing the importance of having the resources to get your supporters to the polling stations, particularly in this election.

"Getting 10 more ballots in a box, getting five more ballots in a box, getting 100 more ballots in a box, is everything in this kind of a close campaign, and will determine who wins this campaign," he said.

NDP Leader Tom Mulcair, accompanied by wife Catherine Pinhas, waves to supporters as he arrives at a rally in Saskatoon on Monday, October 12, 2015. (Ryan Remiorz/Canadian Press)

That includes traditional door-knocking as well as millions of phone calls, emails and texts to those identified as supporters.

"You're talking about sometimes five to 10 contacts per person on election day," Lietaer said.

Ground war

It really is the difference between the air war (the bombardment of political advertisements) and the ground war, said Randi Rahamim, a principal at the Toronto-based communications firm Navigator Ltd.

Liberal Leader Justin Trudeau makes his way through a crowd of supporters during a rally in downtown Port Hope, Ont., on Monday, October 12, 2015. (Paul Chiasson/Canadian Press)

"And many people believe it's all about the ground war," Rahamim said. "The beginning of the campaign should be entirely spent on not only converting votes but identifying voters, identifying who your voter base is. So when it comes time to pull the votes, you know who you're pulling. You're pulling the right people to come out and vote."

Traditionally, in regard to voter identification, it's the Conservatives who have been most successful with their advanced contact data base, Rahamim said. But the Liberals and NDP have since caught up.

"We'll be seeing organizations focusing in on really getting those lists together and getting enough volunteers and having enough money to fund paid volunteers and real volunteers to go out there and mobilize," Rahamim said.

Organizational web

But to pull it off on election day, Tieleman said, you need hundreds of volunteers just in one riding. Perhaps most important are the scrutineers who officially represent their respective parties at polling stations. These scrutineers have access to the lists of names of people who have voted and are able to transmit that information back to the "zone house" — the air traffic control of the riding.

The CBC's Adrienne Arsenault explains what you need to vote in the federal election on Oct. 19. As a rule of thumb: you need a document that shows your current address. 1:30

The level of organization needed to co-ordinate all those people is extraordinary, Tieleman said, let alone taking all the data and translating it in order to identify which supporters need to be called, or have their door knocked on, or need a ride to a poll.

"This is a giant spider web of organization for each party," he said. "And if you have 500 volunteers and the other guy has 50, the party with 50 is severely disadvantaged. They can't possibly know who is voting and they can't possibly get all their votes out."

This is why parties in recent years have pushed to get their supporters to vote in advance polls.

"That's No. 1. Trying to get as many resources off your table today so that you don't have to worry about making those phone calls on election day with the scarce resources you have," Lietaer said.

In this election the parties will be testing a host of get-out-the-vote digital tools, he said.

"Less of a 'Hey Bob, I will come pick you and granny up to vote.' It'll be less that, more Twitter, email, texts, electronic flyers, rather than voting cards on the doors to tell you where to vote."

And when it comes to getting out the vote, Lietaer said you need to make an emotional connection with your supporters. "You're trying to get somebody off the couch, get them out of the house in the car to go and actually do something that you want them to do."

"Ambivalence and apathy are your enemies. Hope, fear, any sort of emotion is your friend. So that's why you're trying to make an emotional connection."