Voters in the British Columbia riding of Nanaimo-Ladysmith will go to the polls today to elect a new member of Parliament.

The seat has been vacant for several months since the NDP's Sheila Malcolmson stepped down for a successful run at provincial politics.

Polls close at 8:30 p.m. local time (11:30 p.m. ET). CBC.ca will have updates on the results after the polls close.

Nanaimo-Ladysmith was created in 2012 when the boundaries of two ridings — one encompassing Alberni and one Cowichan — were redrawn. The two ridings were solidly Conservative and NDP, respectively, meaning the new riding has strong bases for two parties on opposing ends of the spectrum.

Macolmson took the riding by 10 points in the 2015 election, but the Liberals and Conservatives also put up strong and nearly identical showings at around 23 per cent of the vote.

The Green party also captured around 20 per cent of the vote in the last election, and they are a competitive player on Vancouver Island. They've put up strong provincial showings in New Brunswick and Prince Edward Island, and this is the last chance for the party to pick up a second federal seat before the election campaign.

Environmental issues tend to influence votes in this part of the province, and with three parties claiming the left of the spectrum, vote-splitting could factor into the results of this byelection.

The main candidates are:

NDP: Bob Chamberlin, former vice president of the Union of B.C. Indian Chiefs

Conservatives: John Hirst, Sun Life Financial manager

Liberals: Michelle Corfield, a First Nations leader who served as chair of the Nanaimo Port Authority

Greens: Paul Manly, communications specialist and former candidate in this riding

All of the party leaders have made appearances in the riding during the campaign.

This is the fourth federal byelection of the year, after three were decided in February.

In the Feb. 25 byelection, voters preserved the Conservatives' long string of wins in Ontario's York-Simcoe by electing Scot Davidson. The Liberals, with candidate Rachel Bendayan, regained Montreal's Outremont riding, which was held by former NDP leader Tom Mulcair before he resigned as an MP last August.

Current NDP Leader Jagmeet Singh earned a seat in the House of Commons with a win in Burnaby South, which was vacated last September by former New Democrat MP Kennedy Stewart, now Vancouver's mayor.

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