The vote, which will have little effect on the country's bigger political picture, has hardly caught the attention of the wider public, with both polls and pundits suggesting the New Democrats will have no trouble hanging on to Toronto-Danforth.
"You have people who I don't think have completely forgotten the memory of Jack Layton and that will loom significantly over how people choose to cast their vote," said Bryan Evans, a professor of political science at Ryerson University.
"And the reality is: It is a riding with a bit of a tradition for voting for the NDP."
Carrying the standard for the New Democrats is Craig Scott, a law professor, human rights lawyer and neophyte politician.
The Liberal candidate is Grant Gordon, an advertising executive, while the Conservatives are being represented by Andrew Keyes, a communications consultant.
Gordon faces an extra obstacle in that his nomination came late in the game, and only after his losing opponent raised eyebrows by declaring himself pro-life in opposition to the Liberal party's position on women's reproductive rights.
The vote also comes just days before the Opposition New Democrats choose a successor to Layton as party leader.
Still, even though some wondered why leadership contender Brian Topp opted against running in the riding as a way into Parliament, experts suggest the byelection outcome will have no impact on who gets to fill Layton's shoes at the party's helm.
Toronto-Danforth, just to the east of the city's downtown area, is a diverse riding, known for its large Greek, Chinese and other ethnic communities.
Established in 1976, it has deep Dipper roots. Its first incumbent was Bob Rae, the current interim Liberal leader, who held the riding for the New Democrats before moving into provincial politics. Fellow NDPer Lynn McDonald took over from Rae in 1982.
However, in 1988, Dennis Mills won the riding for the Liberals, and held it with large majorities for 16 years before Layton finally ended the former MP's reign by a squeaker in 2004.
In the three elections that followed, Layton proved increasingly unbeatable, taking almost 61 per cent of the popular vote to the Liberals' 18 per cent in 2011.
"It's definitely an NDP riding and Jack was a huge part of building it," Scott said in an interview.
"(Initially) quite a high percentage of the conversations would focus on people's very fond memories of Jack . . . and then it began to shift more towards 'how is it that you will be a worthy successor to Jack?'"
For his part, the Liberals' Gordon said at the start of the campaign, people would tell him, "I voted for Jack, I didn't vote for the NDP, so my vote is up for grabs."
"I heard that a lot at the beginning but I'm not hearing that any more," he said. "People are focused on the future."
Keyes' campaign did not respond to an interview request.
Even if the NDP, according to opinion polls, has seen its national popularity fade somewhat in recent months, surveys suggest Layton-style results will be repeated Monday.
Eight other candidates, including three independents, are also in the race.
About 75,000 people are eligible to cast ballots, with polls closing at 8:30 p.m. eastern.
Currently, the NDP holds 101 seats in the Commons to the Conservatives' 165. The Liberals have 35.
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