TORONTO, Oct 21 (Reuters) - As Canadians head to polls on Monday, Prime Minister Justin Trudeau's Liberals are neck-and-neck with Andrew Scheer's Conservative Party in national opinion polls. The New Democratic Party (NDP) led by Jagmeet Singh and the Green Party led by Elizabeth May are in third and fourth place respectively.
In a close race, a few votes in a few electoral districts, called ridings in Canada, could make all the difference in who is prime minister.
Here is how Canada's system of parliamentary democracy works..
Here are some key ridings that may be indicators for national trends at ballot boxes across the country.
BURNABY NORTH-SEYMOUR, BRITISH COLUMBIA
The Trans Mountain Pipeline is a controversial issue in this West Coast riding. It is held by the Liberals, but they won by only six percentage points over the NDP in 2015. The Trudeau government's decision to buy the project in 2017 is not supported by residents, according to the current Liberal Member of Parliament, Terry Beech, who voted against the purchase.
The NDP is running veteran Svend Robinson, 67, who represented three now-dissolved Burnaby ridings between 1979-2004. Conservative candidate Heather Leung could have potentially benefited from a vote split between the Liberals and NDP, but the party announced earlier this month that they were dropping her after homophobic comments she made in 2016 came to light. Leung remains on the ballot.
CALGARY CENTRE, ALBERTA
The Liberals are hoping to hold onto what is one of only two footholds in Alberta, but anti-Liberal sentiment is running high in the oil-rich province as many feel the governing party has bungled the energy portfolio. Incumbent Kent Hehr flipped this riding from the Conservatives in 2015 by a margin of 1.2 percentage points. He was originally a cabinet member, but resigned in 2018 in the wake of sexual harassment allegations. Polls indicate he is facing a tough reelection campaign against Conservative candidate Greg McLean.
CHURCHILL—KEEWATINOOK ASKI, MANITOBA
The NDP currently hold this riding, but only just - in 2015 then-two term incumbent Niki Ashton won 45% of the vote versus 42% for the Liberals. This year the Liberals are fronting Judy Klassen - who unseated an NDP minister in the same riding in the 2016 provincial election - to face off against Ashton. With the highest proportion of indigenous voters anywhere in Canada, the riding is expected to be an indicator of whether Trudeau can repeat his 2015 success of connecting with aboriginal communities and motivating them enough to get to the ballot box.
Located in central Toronto, this current Liberal riding was held by the popular NDP Leader Jack Layton until his death in 2011. Liberal Julie Dabrusin took it in 2015 by a margin of just 2 percentage points. Voters are predominantly middle class with post-secondary education, and a high proportion of immigrants, according to 2016 Census data. This makes it a key battleground for the progressive vote between the Liberals and NDP. The leaders of both parties have made campaign stops here, a sign they consider it a target.
ETOBICOKE NORTH, ONTARIO
Located just outside of Toronto, this riding is currently held by the federal Liberals and usually considered safe for them. It's also the provincial riding of Ontario's Conservative premier Doug Ford, who has fallen in public opinion polls since coming to power in 2018. Ford flipped the riding from the provincial Liberals last year. Although neither his party nor the Ontario Liberals are affiliated with their federal counterparts, voter support for the provincial party often reflects in support for the federal iteration. The riding will be seen as an indicator of whether the federal Conservatives will be hurt by the premier's falling popularity in Canada's most populous province.
The situation is further complicated by Ford's sister-in-law, Renata Ford, widow of the late Toronto mayor Rob Ford who was best known for admitting in 2013 he had smoked crack cocaine while in office. She will be on the ballot for the right-wing People's Party of Canada.
This southern Ontario riding represents a mix of voters - urban and rural, young university students and older retirees, predominantly white and English-speaking but with a growing population of Syrian refugees and other minorities. It has been a bellwether for almost every election result in its 66-year history. Incumbent Maryam Monsef, a Liberal cabinet minister, is facing off against the Conservatives' Michael Skinner, who lost to her in 2015 by just over 8 percentage points.
The rural central Quebec riding is held by the NDP, but it's a close four-way race, pollsters say. The New Democrats won it in 2015 with 28.7% of the vote, with the Liberals just behind on 27.6%. The separatist Bloc Quebecois party came third with 24.3% of the vote, and the Conservatives trailed with 16.7%. Composed almost exclusively of French-speaking voters and few immigrants, this heavily agricultural region is a target for all four parties - with the NDP's support in the province lagging, the others see it as an opportunity.
Maxime Bernier held this riding for the Conservatives between 2006 and 2018, when he resigned to create the People's Party of Canada after losing the leadership contest of the Conservative Party to Scheer. The Conservatives are running a former mayor and local businessman Richard Lehoux, whose family have been dairy farmers for four generations. (Reporting by Moira Warburton; Editing by Alistair Bell)
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