Should they vote for the right-leaning Progressive Conservatives in order to prevent the further-right Wildrose party, ahead in the polls, from winning government?
NDP and Liberal supporters in past elections, particularly in urban areas such as Edmonton, have debated whether to get behind each other's candidates to unite against the Tories. But with the prospect that four-decade Tory dynasty could fall to the Wildrose, grassroots campaigns have emerged urging lefties to hold their noses and vote Progressive Conservative in order to keep the Wildrose out.
An Internet video called "I can't believe I'm voting PC," which features actors portraying NDP or Liberal supporters saying they'll vote Tory this time around, has gone viral. Meanwhile, a satirical meme is making the rounds on the Internet featuring a photo of actor Keanu Reeves, star of The Matrix movies, pondering whether the Progressive Conservatives invented Wildrose in order to get Liberals to vote for them.
University of Calgary political scientist Doreen Barrie says strategic voting has always been an issue for left-of-centre voters, but it's better organized this time around. She says it's likely due to frustration with the first-past-the-post electoral system and the skewed legislatures it produces.
Progressive Conservatives, she explains, have only achieved an average of 55 per cent popular support in provincial races over the last 40 years, and that support has never gone higher than 63 per cent. Yet opposition parties typically only win a handful of seats.
Barrie says there's no way to predict what kind of effect strategic voting will have on Monday, saying she's not aware of any studies on it.
"If the vote for the other parties collapses and the vote for the Conservatives goes up, then I think you can gauge from that it has been successful," Barrie says.
Strategic voting is not without its risks.
In the 2011 federal election, NDP supporter Dale Ladouceur says she voted for a Liberal because she believed the candidate had a better chance of defeating the incumbent Conservative MP. But when the results rolled in, the incumbent still won and the NDP candidate Ladouceur favoured actually polled better than the Liberal she voted for.
"You must vote with your heart," says Ladouceur. "I remember walking out of the polling station feeling kind of dirty. 'I said I'll never do that again.'"
Not surprisingly, leaders of the Liberals and the NDP are pleading with their supporters to reject strategic voting.
Liberal Leader Raj Sherman and NDP Leader Brian Mason both say strategic voting would produce a right-wing government with a right-wing opposition.
Sherman issued a news release over the weekend claiming that even if the Tories under Alison Redford win, the margin of victory will be small. He says the PC party will likely then shift right in an effort to regain the votes it lost to Wildrose.
"People may think they're voting for Redford, but she'll be way past her best-before date the moment the polls close," Sherman says in the release. "If she doesn't resign right away, her days will definitely be numbered."
Redford isn't personally asking for redirected votes, but has said she can work with the NDP and Liberals in the legislature.
Wildrose leader Danielle Smith, meanwhile, says strategic voting would mean the Progressive Conservatives would form government again.
A website called ChangeAlberta.ca rejects voting Tory to block Wildrose, and lists progressive candidates with the best chances of defeating conservatives, be they PC or Wildrose.
"Abandoning the centre-left parties at the polls now will not stop the PCs or the Wildrose from implementing damaging legislation on health care, education, and the environment," the site states.
Barrie says the over-representation of right-wing parties in Alberta's legislature is part of the reason for Alberta's dismal voter turnout in provincial elections. Just under 41 per cent of eligible voters bothered to go to the polls last time. She adds that Conservatives also typically stay home because they believe that victory for them is a done deal.
"It's a very poor way of reflecting voter preferences, our electoral system. And people judge the province by the size of the Conservative majority in the legislature," she says.
It's likely to be different this time, she says, with such an unpredictable outcome.
Barrie adds that supporters of left-of-centre parties might want to consider the effect their votes might have if Monday's vote produces a minority government.
"If people from the non-Conservative parties did vote strategically and get seats, if it's a minority government, then they would have some clout."
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