It has also been cast as the first test of how fledgling Liberal Leader Justin Trudeau and NDP Leader Thomas Mulcair stack up on the campaign trail.
Henry White, who runs Bert's Barber Shop in Happy Valley-Goose Bay, knows how he'll vote.
"Everybody makes mistakes," he said of Conservative incumbent Peter Penashue, who stepped down as intergovernmental affairs minister over ineligible campaign donations accepted in 2011. "I didn't vote for him before but this time I'm going to give him a chance.
"I think he did a lot for Labrador," White said during a break from trimming hair. He said his male clients in Labrador's largest town overwhelmingly agree with him.
"What are we going to do with a backbencher? Yvonne or Harry? We're not going to get nothing."
Liberal candidate Yvonne Jones is a former provincial Liberal party leader and 17-year veteran of the legislature, while Harry Borlase is a political newcomer and NDP hopeful.
Penashue has unabashedly declared that his re-election would mean a spot back in Prime Minister Stephen Harper's cabinet. The implied advantage of such inclusion in the government's inner circle was underscored last week by Defence Minister Peter MacKay, the Conservative party's deputy leader.
He said last Monday while campaigning in Happy Valley-Goose Bay that Penashue's cabinet reappointment is "a guarantee" that's the difference between yelling at Harper in Parliament or sitting across the table from him.
Jones dismisses such tactics as "fear mongering."
"You know it's the rhetoric of fear that they try and penetrate the voters with and most people don't buy into it," she said in an interview. "Most people are sick and tired of it.
"People have had enough of it and they want a change."
It's a message echoed by Borlase, a northern issues analyst and researcher, who said voters around the vast and often isolated riding have repeatedly said they want action on housing, social issues, the environment and pension concerns.
"People are warming up to us and liking the idea that it's not just a two-horse race in Labrador politics anymore," he said in an interview.
Penashue did not respond to interview requests but has said he stepped down to acknowledge campaign overspending in 2011 and regain the trust of voters.
Elections Canada records show he exceeded his campaign spending limit of $84,468.09 by $5,529.76 while also accepting tens of thousands of dollars in off-limits donations. They included cash from 16 listed corporations and non-monetary contributions from two airlines that flew him around the riding.
Elections Canada now says Penashue's 2011 campaign return is final after repayments of almost $48,000, but it's not known if files were referred to the Commissioner of Elections. The commissioner can issue compliance orders or seek criminal charges through the Office of the Public Prosecutor.
Spokeswoman Diane Benson said Elections Canada does not comment on individual files. Any charges stemming from investigations are made public when the commissioner issues a news release, she said.
Conservative strategist Tim Powers, vice-president of Summa Communications, said Penashue's supporters in Ottawa are "realistic" about his chances of winning.
"I think Conservatives accept that it has always been a bit of an uphill battle in Labrador," he said of a riding that has gone Liberal in every federal election but two since the province joined Confederation in 1949. "And it's certainly going to be an uphill battle on Monday for Peter Penashue to get re-elected."
Even with an uneven financial playing field, Penashue barely beat Liberal incumbent Todd Russell in 2011 by 79 votes to give the Conservatives their only victory in the province. Russell chose not to run again.
Powers believes Penashue's big mistake was not stepping down sooner.
"I think he needs to be commended for doing the right thing, I just think had it happened sooner that it may have helped."
That said, Powers said Penashue should not be written off. "He's a pretty skilled fighter and he does still have a good complement of people who support and admire him."
Kelly Blidook, a political scientist at Memorial University of Newfoundland, said promises of a cabinet post for Penashue can be seen as a sign of Conservative desperation.
"I think it's a tough battle for him because he's quite clearly been seen to have broken rules that we think of as pretty fundamental to democracy. It's hard for people to turn around and say: 'Well, that's okay.'"
Conservative efforts to reinforce the notion that government support equals a greater share of taxpayer-funded largesse is a typical but unfortunate ploy, Blidook said.
"Most people, I think, are cynical at best if not outright distrusting of public officials, and these are the sorts of things that cause it."
Norman Andrews is also running for the Libertarian party. Green party Leader Elizabeth May said her party will have candidates across Canada in the next general election. But the Greens opted not to run in the Labrador byelection in an effort to co-operate against left-wing vote splitting, and she urged the NDP to do the same.
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