OTTAWA - Canadians go to the polls Monday with the option of choosing to "stay the course" with the Conservatives or plump for change touted by the Liberals and New Democrats, in legislative elections too close to call.
In power since 2006, Prime Minister Stephen Harper is seeking a fourth mandate, hoping to hold onto key Conservative support in the western plains and in suburban Toronto, Canada's largest city.
But the 56-year-old faces stiff opposition from his emboldened rivals.
In the one corner is Liberal leader Justin Trudeau, 43, the son of former prime minister Pierre Trudeau, who is considered the father of modern Canada.
The Liberals have sneaked ahead in the most recent opinion polls.
In the other corner is Thomas Mulcair, 60, head of the New Democratic Party (NDP) and looking to build on a second-place finish in the last ballot, in 2011, and govern for the first time ever.
The social democrats started the campaign - one of the longest in Canadian history - in July as the frontrunner, promising new social spending but no budget deficits or tax hikes.
But the NDP stumbled in the final straight, losing key support in Quebec province over its opposition to a popular ban on the veil. That allowed the Liberals to come from behind to take the lead by wooing progressives.
The NDP has also been fighting off the chipping away of its support by the separatist Bloc Quebecois and the Greens.
Mulcair, a charismatic orator and former lawyer, insisted in the final days to voting that the race remained too close to call - as it was throughout most of the campaign.
"For the first time in Canada it's a three-horse race," he said.
Harper echoed that Thursday, saying: "It's a tight election."
Polls showed the Liberals gained five percentage points in the past week and now have 35 to 37 percent support, which would be enough to form a minority government come Monday.
The Tories' base support has remained relatively stable at about 31 percent, but Harper faces strong headwinds: the electorate's natural desire for change after nine years of Tory rule and a weak economy that fell into recession at the start of the year on the plunging price of oil.
Harper stepped up his game in recent weeks, attacking the Liberals' economic platform that includes tax hikes and deficit spending on new infrastructure and social programs.
The youthful-looking Trudeau throughout has been combative, fending off attacks that he is "just not ready" to be prime minister and hammering opponents in election debates on the economy, Canada's reputation and the environment.
He and Mulcair accused Harper of not doing enough to help Syrian migrants as a crisis unfolded in Europe with a record influx of people fleeing war in Syria.
Both pledged to take in more migrants if elected, while Harper stressed that the key to ending the crisis was to defeat the Islamic State group.
The New Democrats said they would end Canada's military mission, while the Liberals said they would withdraw Canadian war planes, but continue training forces in Iraq.
About 26.4 million voters are registered to cast a ballot in 338 electoral districts and turnout is expected to be high after advance voting jumped more than 70 percent from the last ballot.