- British Columbia: North Vancouver
- Prairies: Calgary Skyview, Edmonton Centre, Lethbridge, Regina-Lewvan, Saint Boniface-Saint Vital
- Ontario: Ajax, Eglinton-Lawrence, Guelph, Kenora, London West, Mississauga Centre, Ottawa West-Nepean, Scarborough Southwest, Spadina-Fort York
- Quebec: Ahuntsic-Cartierville, Avignon–La Mitis–Matane–Matapédia, Laurier-Sainte Marie, Louis-Saint-Laurent, Mont-Royal, Rimouski-Neigette–Témiscouata–Les Basques
- Atlantic: Bonavista-Burin-Trinity, Cumberland-Colchester, Fredericton, St. John’s South-Mount Pearl
Conservative Andrew Saxton, parliamentary secretary to the finance minister, won this riding with 48 per cent of the vote in 2011, but acknowledges it has tilted Liberal in past. Despite a long Conservative history, Liberal Don Bell held the riding for two terms until defeated by Mr. Saxton in 2008. In 2011, the Liberals won 30 per cent of the vote and the NDP 17 per cent. Now Mr. Saxton considers North Vancouver a swing riding. "I know this is a target riding of the Liberals because they did hold it from 2004 until 2008," he says. That puts businessman Jonathan Wilkinson, the Liberal candidate, in play. The NDP candidate is native activist Carleen Thomas. Former CBC meteorologist Claire Martin is running for the Green Party.
Why this riding matters: Because of substantial redistricting throughout Calgary's 10 ridings, incumbents like Conservative MP Devinder Shory are facing an added layer of insecurity this election. Mr. Shory has held the city's northeastern-most riding since 2008, however, his latest nomination win was marred when his two challengers were disqualified without explanation. His main challenger will be Liberal Darshan Kang. A former MLA who was considered an effective, albeit discreet, organizer, he kept the area from the provincial Conservatives from 2008 until this May when Rachel Notley's orange wave rolled through.
JASON FRANSON For The Globe and Mail
Why this riding matters: With incumbent Conservative MP Laurie Hawn stepping down, the riding could be a three-way race. Former Edmonton Chamber of Commerce CEO James Cumming has had most of a year to build a rapport between electors in the downtown riding and the Tories. He'll face NDP candidate Gil McGowan. The head of the Alberta Federation of Labour for a decade, Mr. McGowan is a well-known activist with deep connections to Rachel Notley's NDP. The riding has also had a history of electing Liberals and Randy Boissonnault could be his party's best opportunity in northern Alberta.
Why this riding matters: The deeply conservative belt south of Lethbridge has been cut out of this redrawn riding for the 2015 election, leaving only the university town and the area around it. The New Democrats have had their eyes on the riding since a promising result in 2011. With incumbent Conservative MP Jim Hillyer choosing to run in a neighbouring rural riding, local volunteer Rachael Harder will need to fend off the NDP's Cheryl Meheden, a grocer and former mayoral candidate.
Why this riding matters: As Canada's map of riding boundaries was redrawn, Saskatchewan was the site of the most bitter battles. For many years, ridings had a mix of urban and rural populations and Conservative support outside cities typically outweighed urban votes for other parties. Not so with the new boundaries. This new Regina riding features a contest between labour economist Erin Weir running for the NDP and the Conservatives' Trent Fraser.
Why this riding matters: Cabinet minister Shelly Glover made history in 2011 by becoming the first Conservative to win re-election in this riding. But now she is retiring from politics to return to policing, leaving the south Winnipeg seat open. Businessman Francois Catellier replaced her as the Conservative candidate, but he will face a strong challenge from former city councillor Dan Vandal.
CHRIS WATTIE for REUTERS
Why this riding matters: It's a 2011 rematch: cabinet minister and former diplomat Chris Alexander versus Mark Holland, who held the suburban riding for the Liberals for seven years. Both have been hailed as rising stars within their parties, and both have seen early support from federal leaders dropping by. It will be a bitter campaign for those working the doors in the riding.
Why this riding matters: This urban Toronto riding has long been a two-party battle between Conservatives and Liberals. Joe Oliver defeated veteran Liberal candidate Joe Volpe in 2011 and went on to become federal finance minister. Marco Mendicino won the Liberal nomination this time, defeating former Conservative MP Eve Adams in her attempt to switch parties. However the NDP shook things up early in the campaign by announcing Andrew Thomson, a former finance minister in Saskatchewan, would be running here. The party has been promoting Mr. Thomson heavily since and he regularly speaks for the party on television panels, but the NDP only received 11.6 per cent of the vote here in 2011.
Why this riding matters: This is one of the races observers will be watching not for the outcome – the Liberals are expected to hold it for an eighth straight election – but for what happens during the campaign. Guelph was ground zero for deceptive robocalls, where opposition supporters received misleading automated calls directing them to incorrect polling stations. One Conservative staffer, Michael Sona, was sentenced to prison for his role. Reports of fraudulent calls in other ridings were never proven.
Why this riding matters: A trio of political heavyweights is battling it out for the right to represent the northwestern Ontario of Kenora. Natural resources minister Greg Rickford is hoping to hold the seat for the Conservatives, but he is up against a couple of big names. Former Liberal cabinet minister Bob Nault is running again, while Howard Hampton, the former leader of the Ontario NDP, is running for the New Democrats. The riding's First Nation communities could play a key role in the outcome. All three parties have had political success in the region over the years.
Why this riding matters: This southwestern Ontario riding has been a fairly reliable bellwether over the years, swinging between Liberal and Conservative at the local level at the same time as governing parties changed in Ottawa, in 12 of the past 14 elections. Conservative Ed Holder, only recently named to cabinet, is seeking re-election in what's looking like a three-way race. The NDP won the riding in last year's provincial election, and is now trying to make a federal breakthrough in the region.
Why this riding matters: The Greater Toronto Area is one of the fastest growing regions of the country by population, and that's being recognized in Parliament: with the redistribution of seats that happens every decade based on the census, the GTA alone gets nine of the 30 new seats in the House of Commons. Mississauga Centre is a prime example of a riding the Liberals will have to retake from the Conservatives if they have a chance of forming government.
Why this riding matters: The Conservatives have nominated police officer Abdul Abdi to replace John Baird, one of Stephen Harper's most senior cabinet ministers. Mr. Baird took this riding for the Conservatives in three straight votes, but now that he's retired from politics, this suburban-rural riding could be wide open.
Why this riding matters: It was one of the closest three-way races in the country, with the NDP, Conservatives and Liberals all finishing within six points of each other and New Democrat Dan Harris taking the seat with 35 per cent of the vote. And this time he's got a high-profile challenger: Bill Blair, Toronto's former police chief, who is carrying the Liberal banner. Mr. Blair's experience will make security and Bill C-51, the anti-terror law, a hot election topic.
This downtown Toronto riding represents a potential comeback for Olivia Chow, the former NDP MP who quit to run unsuccessfully for Toronto mayor in 2014. But her former riding is different now: gone are the student-heavy neighbourhoods around the University of Toronto, in favour of more waterfront condo dwellers. And she faces a formidable challenger: Liberal MP and former city councillor Adam Vaughan, who in an upset won the by-election to replace her.
Graham Hughes for THE CANADIAN PRESS
Why this riding matters: Maria Mourani has won the riding in every election since 2006 as a candidate for the Bloc Québécois. She has since crossed the floor to the NDP, where she will try to win the seat that did not break for the Orange Wave in 2011. Her main rival is Liberal candidate Mélanie Joly, who finished second in the 2013 mayoral race in Montreal. However, she had to go through a tough nomination fight to win a spot on the ballot.
Why this riding matters: Jean-François Fortin won the riding for the Bloc Québécois in 2011 with only 36 percent of the vote. He has since left the Bloc and formed a party called Strength in Democracy that aims to provide a greater voice to rural parts of the country in the House. The race is now on between the Bloc, the NDP, the Liberal Party and Mr. Fortin.
Ryan Remiorz for The Canadian Press
Why this riding matters: Bloc Québécois Leader Gilles Duceppe could not hold on to his seat in the 2011 election as his party was reduced to a four-member rump in the House. He resigned on election night – but announced a comeback earlier this year. Voters will decide whether to send the Bloc Leader back to Ottawa, or keep NDP MP Hélène Laverdière, who was one of her party's critics on foreign affairs.
Why this riding matters: The NDP swept all ridings in Quebec City in 2011, and the Conservatives want them back. The party's best known candidate in the area is Gérard Deltell, a former journalist and well-known MNA. Odds are high he will win the riding that was in Conservative hands between 2006 and 2011, but the question is whether Mr. Deltell can help his party win other seats in the provincial capital.
Why this riding matters: The Conservatives have failed to gain a foothold in Montreal under the leadership of Stephen Harper. Every year, they focus their energies on this riding with a large Jewish community, and they are getting closer. Long-time Liberal MP Irwin Cotler has retired, leaving big shoes to fill… and a wide open race between Liberal candidate Anthony Housefather and Conservative candidate Robert Libman.
Why this riding matters: This riding covers an area of eastern Quebec along the south shore of the St. Lawrence river. It was previously represented in Parliament by Guy Caron, who serves as Quebec Caucus Chair for the New Democratic Party.
Why this riding matters: Bonavista–Burin–Trinity is a new riding for the 2015 election. It covers an area of Newfoundland formerly included in the old ridings of Random—Burin—St. George's and Bonavista—Gander—Grand Falls—Windsor as well as the redrawn Avalon riding.
Why this riding matters: This rural Atlantic riding has been won by the Conservatives in almost every election for 50 years. But this vote could be different: long-time former Tory MP Bill Casey is running against his successor, Scott Armstrong. Mr. Casey quit the Conservatives in 2007, won re-election as an independent in 2008, and is now running for the Liberals, who have been leading polls in the region.
Why this riding matters: Almost every national party leader has visited this riding, which could be one of the closest races in the province. Conservative incumbent Keith Ashfield, who stepped down from cabinet during a recent battle with cancer, is facing former Liberal staffer Matt DeCourcey and Sharon Scott-Levesque, a nurse running for the NDP. And though the Greens are unlikely to win the seat, this could be their best showing in Atlantic Canada. Last year, a Fredericton riding went Green in the provincial election, the party's first win ever in the region.
Why this riding matters: This riding, one of the eastern-most in the country, has a rare distinction: a different party has won in each of the last three elections. The main contest will be between NDP incumbent Ryan Cleary, a former journalist, and Liberal challenger Seamus O'Regan, who hosted CTV's Canada AM for a decade from Toronto. The Conservatives have nominated few candidates in the province a month into the campaign.