The Liberals have a remarkable 29-point lead in the Brandon-Souris riding, according to a last-minute poll.
But questions about Forum Research's survey methodology, and the volatility of byelection turnouts, still make the Westman riding too close to call in today's set of federal byelections.
Forum released its latest round of polling late Sunday night following calls into the riding during the day. The survey has a relatively small sample size but suggests Liberal Rolf Dinsdale enjoys 59 per cent support, a commanding lead over Conservative Larry Maguire's 30 per cent.
But, several Brandon-Souris residents report being polled multiple times throughout the campaign as Forum conducted several waves of polling using random, automated robocalls, where voters indicate their candidate preference using their touch-tone phone.
Brandon resident Anne Ross has received six calls from Forum since the campaign began, raising questions about the poll's reach and its randomness. Ross was called for each of the five polls released so far, including the latest one. She also received a call on Saturday as part of a poll that has not been released.
"I don't know why I would keep getting called," said Ross, a Liberal.
Ross is the mother of Free Press opinion columnist Deveryn Ross, who said he has been called by Forum Research six times during the campaign, including three times since Friday night.
Two other voters who spoke to the Free Press Sunday, including one Conservative, said they also received multiple calls from Forum Research.
There are 62,000 registered voters in the riding.
Forum president Lorne Bozinoff calls interactive voice-response polls "amazingly accurate." He said while it's unusual someone might get called six times in a random poll, he doesn't believe that undermines the poll's results.
"I don't, but we're going to know Monday night for sure," Bozinoff said.
Interactive voice-response polls require far more calls to cobble together a reasonable response rate of at least 400 answers. They are relatively inexpensive, which could account for the coincidence of multiple calls to the same numbers.
Brandon-Souris has been the most watched of four byelections to be decided today, including one in the Provencher seat long held by former Conservative cabinet minister Vic Toews.
That seat is widely expected to remain Conservative, but Brandon-Souris has turned into an unexpected battle. Conservative candidate Larry Maguire, a former MLA, has been dogged by a divisive nomination fight and significant voter anger over the Senate spending scandal.
Meanwhile, the Liberals have been buoyed by the buzz around rookie leader Justin Trudeau, who has visited the riding three times during the campaign. Both Trudeau and Liberal candidate Rolf Dinsdale have been the targets of a recent wave of negative flyers distributed by the Conservatives.
Forum's polls have bolstered the perception that Brandon-Souris is a tight race, one that could cause Prime Minister Stephen Harper significant damage should the Conservatives lose.
The four polls have been consistent, showing the Liberals with growing momentum earned largely from a collapse of NDP and Green popularity. When the byelection was called Oct. 20, Dinsdale had 39 per cent support, according to the first Forum poll. Dinsdale's support has now grown by an almost unbelievable 20 points.
With political polling under scrutiny, thanks to dramatic failures in recent provincial and federal elections, Probe Research's Curtis Brown said it's more important than ever for pollsters to get it right and be open about their methods.
"It does seem very strange to get your phone number drawn every time," Brown said. "That raises some concerns about the validity."
Probe Research polls often for the Winnipeg Free Press.
In Brandon-Souris, which has voted Tory for most of the last 60 years, the Liberals now enjoy more support than they do in another riding up for grabs today -- Toronto Centre. There, Forum's Sunday night poll suggests Grit candidate Chrystia Freeland has 47 per cent of the vote in a riding that's voted Liberal for the last 20 years and was last held by former interim party leader Bob Rae.
Today's fourth byelection is being held in the northern Montreal riding of Bourassa.
It is difficult to accurately predict the outcome of a tight byelection race because turnout is widely seen as the deciding factor. Bozinoff cautions that a strong get-out-the-vote machine -- which the Tories have in Brandon-Souris -- could easily undercut Forum's latest findings. In the waning hours of the campaign, all parties will be working full-bore to alter the outcome.
Polls close today at 8:30 p.m. For voting information, visit www.elections.ca or call Elections Canada at 1-800-463-6868.