The residents of the ridings of Palliser in Saskatchewan, Oshawa in Ontario and Surrey North in British Columbia - and 35 other Conservative-held constituencies across Canada - are about to get a phone call.
In a "polite, nice" way, a recorded voice will urge them to vote for anyone but the incumbent Tory MP on Monday.
It's a plea that does not come from a political party. It is the work of a grassroots citizens group with a strong Internet presence called Catch 22. As in: Catch 22 Conservatives.
"I know we would feel wonderful if we could see the results come out on election day and we could feel that we might have made a difference in six or eight seats," said Nick Fillmore, one of the group's strategists. "We think that might be enough to stop a majority government."
Catch 22 is not alone. The Internet offers unlimited opportunities for ordinary citizens to become politically engaged. And Canadians - particularly, it seems, those with a desire to thwart Conservative Leader Stephen Harper - are taking advantage of them.
Some websites advocate vote swapping. A person who supports the Liberals in a riding that is a lock for that party, for instance, offers to vote for a Green or an NDP candidate if a supporter of one of those parties in another riding, where the Liberals could win but need help, votes Liberal.
Some simply urge younger Canadians, who traditionally skew to the left, to get to a polling station.
Others, like Catch 22, promote strategic voting. The group picked ridings where it believes a Conservative MP can be defeated and others where a Conservative can make gains. It then endorsed the candidate - Liberal, NDP or Bloc Québécois - best positioned to come out on top.
There is no party affiliation, Mr. Fillmore said. "The overriding thing is which candidate has the best chance of defeating a Conservative."
Conservative bloggers have had a significant presence on the Internet for a number of years, easily out-distancing the Liberals and the NDP in terms of their numbers and their ability to share information through sites like The Blogging Tories.
But in this campaign, the anti-Conservative sites have dominated the online discourse.
One of the videos on a scatologically named website, accessible through an "old-folk-friendly" link at www.rubbishharperdid.com, features young people trying to persuade others to vote against the Tories. It was the most shared YouTube clip in Canada on the day it was released, edging out Lady Gaga. By Tuesday of this week, it had been uploaded nearly 600,000 times.
Another video that went viral was that of the University of Guelph's Vote Mob - students running around campus to the beat of inspiring music with signs saying, "Surprise: We are voting."
The Guelph students challenged their counterparts at other campuses to create their own vote mobs, and at last count, 17 similar videos created at universities from Victoria to St. John's were posted on the website leadnow.ca.
Gracen Johnson helped organize the first vote mob in Guelph.
"The Canada that I am proud of is not the Canada that I am living in right now, so I would like to restore the country that I feel proud of. And I think the way to do that is to engage people who are educated, informed, to vote," Ms. Johnson said.
But will these Internet offerings have an effect at the polls?
Royce Koop, a post-doctoral fellow at Queen's University in Kingston whose expertise is political communication, is doubtful.
Some of them, like the Catch 22 site, make good use of the technology, he said, so they may have an impact.
As for the vote mobs, Dr. Koop said anything that gets young people out to vote is a good thing.
But other anti-Conservative sites "just look like a bunch of hipsters talking to one another. It's creative people using Harper as their muse to do creative things," he said.
"And they are largely preaching to the converted. They should get out from behind their computers and actually join a campaign if they want to beat Harper."
So, why have anti-Conservative websites proliferated?
Dr. Koop said it's partly related to demographics. Conservative supporters tend to be older than those who actively back other parties and that means they are less likely to be regular viewers of YouTube.
It's also a function of the message. The sites are aimed at increasing participation, but also preventing vote-splitting, which is not an issue for the Tories.
It could also relate to the fact that grassroots movements tend to target the party that is in government, Dr. Koop said.
And it could be Mr. Harper himself. "The image that he is projecting as the suburban dad … it just seems to be custom-built for people to come along and say how uncool the party is," Dr. Koop said.
But Gerry Kirk, the spokesman for Pair Vote, one of the vote-swapping sites, said the motivation is much more simple than that: it's about democracy.
"We're trying to align the election results with what the voter intentions are," Mr. Kirk said.
"There are one million voters who vote Green, they have no representation. That's wrong. We have the potential for a party, in this case the Conservative Party, to get a majority with less than a majority vote. That's wrong."