Avalon: Ex-Liberal Scott Andrews running as an Independent after leaving the Liberal caucus earlier this year when he became the subject of an unproven sexual harassment allegation. The Liberals are putting up Ken McDonald, the mayor of Conception Bay South, to keep the seat in this redrawn riding.
St. John's South-Mount Pearl: The NDP incumbent Ryan Cleary faces a tough fight from a star Liberal candidate, Seamus O'Regan, a former host of CTV's Canada AM morning television program.
PRINCE EDWARD ISLAND
Egmont: Conservative cabinet minister Gail Shea is caught in a tight three-way fight. Her party isn't polling well in the province, and its proposed changes to EI aren't popular either. Traditionally, the riding has been a Liberal stronghold. The Liberal candidate, Robert Morrissey, and the NDP candidate, Herb Dickieson, have previously won seats in the provincial legislature.
Madawaska-Restigouche: Conservative cabinet minister Bernard Valcourt has faced some tough campaigning. NDP candidate Rosaire L'Italien and Liberal candidate Rene Arsenault have pushed the veteran Conservative hard during all candidates debates in the predominantly French-speaking riding outside Quebec.
Central Nova: Former Conservative party president Fred DeLorey tries to hold Peter MacKay's old seat against Liberal Sean Fraser and NDP Ross Landry. MacKay, who has deep roots in the riding and was the Conservatives' Atlantic Canada lieutenant, has been reportedly campaigning hard on behalf of DeLorey.
Cumberland-Colchester: Conservative incumbent Scott Armstrong faces a challenge from newly minted Liberal Bill Casey, a former Conservative who was kicked out in 2007 after accusing Stephen Harper of breaking promises to Atlantic Canada. Liberal Leader Justin Trudeau and former prime minister Jean Chretien have dropped in on the riding during the campaign.
Lac St. Jean: Conservative cabinet minister Denis Lebel holds one of only five Tory ridings in the province. He is facing NDP challenger Gisele Dallaire, Liberal Sabin Simard and Bloc Quebecois Sabin Gaudreault. NDP Leader Tom Mulcair campaigned in the riding recently.
Ahuntsic-Cartierville: Liberal Melanie Joly is battling the NDP's Maria Mourani. Joly is well known to Montreal voters after finishing second for the mayor's job in 2013. She's also considered to be a friend of Justin Trudeau. Mourani is an ex-Bloc MP who crossed the floor earlier this year.
Berthier-Maskinonge: The NDP's Ruth Ellen Brosseau faces a tough challenge from Liberal and Bloc Quebecois candidates. Brosseau faced criticism for spending part of the 2011 campaign in Las Vegas. But she has worked hard to win the confidence of her constituency.
Laurier-Sainte-Marie: Bloc Quebecois Leader Gilles Duceppe is running against the woman who beat him in 2011: the NDP's Helene Laverdiere. The riding represents a major test for the Bloc to see if it can regain support lost to the NDP four years ago. In the last week of the election, Duceppe and Laverdiere appeared to be in a dead heat.
Ajax: Conservative cabinet minister Chris Alexander and Liberal Mark Holland are in a grudge match of sorts. Alexander unseated Holland in 2011, becoming one of the Conservatives' fiercest partisans, and has overseen some hot-button issues as immigration minister, including controversial changes to the citizenship law and the niqab issue.
Eglinton-Lawrence: Finance Minister Joe Oliver has been campaigning hard to keep his seat from Liberal challenger Marco Mendicino ,who won a tough nomination in his own party over former Conservative floor crosser Eve Adams. The NDP is running a star candidate of its own, former Saskatchewan finance minister Andrew Thomson.
Orleans: Retired general Andrew Leslie is carrying the Liberal banner in this suburban Ottawa riding in an attempt to unseat Conservative Royal Galipeau, who has held the riding since the Conservatives won power in 2006. Leslie commanded the Canadian army during its bloodiest period in Afghanistan, and is a foreign policy adviser to Justin Trudeau.
Sarnia-Lambton: This is a bellwether riding, having elected the winning party's candidate in every election since 1963. Pat Davidson has held the riding since the Harper government won power in 2006. But she's not running in this election. The Conservatives are fielding Marilyn Gladu to run against Liberal David McPhail and the NDP's Jason McMichael.
Elmwood-Transcona: Long-time New Democrat Bill Blaikie held the riding for two decades before retiring in 2008. Now his son, Daniel, is trying to win back the riding from Conservative Lawrence Toet.
Winnipeg South Centre: Conservative MP Joyce Bateman won the riding from the Liberals in 2011, which held it since 1988. Liberal Jim Carr and the NDP's Matt Henderson are fighting the incumbent.
Saint Boniface-Saint Vital: Former Conservative Heritage Minister Shelly Glover quit politics, creating a vacancy that has sparked a three-way race for the seat. The NDP has fielded former provincial MLA Erin Selby while the Liberals are running long-time municipal politician Dan Vandal while the Conservatives are counting on long-time resident Francois Catellier to hold the seat for them.
Saskatoon West: This is a new urban riding that the New Democrats are hoping to claim because they polled well in the city portion of the old riding in 2011. The Conservative incumbent, Kelly Block, has moved to an adjacent rural riding. The NDP's Sheri Benson, Liberal Lisa Abbott and Conservative Randy Donauer are vying for the seat.
Regina Lewvan: This is a new urban riding that's giving high hopes to the NDP, which has outpolled the Conservatives in the urban sections of the riding. New Democrat Erin Weir carries his party's hopes against Liberal Louis Brown and Conservative Trent Fraser.
Desnethe-Missinippi-Churchill River: Conservative MP Rob Clarke won this northern Saskatchewan riding in 2011. But redistribution is once again playing against the Conservatives because under its new boundaries, his margin of victory would have been much slimmer. The NDP is fielding Georgina Jolibois, a former area mayor, while Lawrence Joseph, the NDP candidate in 2011 is now running for the Liberals.
Calgary Centre: Conservative Joan Crockatt won narrowly in a 2012 byelection over a Liberal challenger. This time the Liberals and NDP are hopeful they can score a victory in the heart of Conservative country. Liberal Kent Hehr, a former Alberta MLA, is running against the NDP's Jillian Ratti.
St. Albert-Edmonton: Brent Rathberger is running as independent after quitting the Conservatives because of too much PMO control. But a recent poll had Conservative Michael Cooper ahead of Rathberger, with the NDP and Liberal candidates trailing them.
Edmonton Griesbach: This new urban riding is raising NDP hopes of an Alberta breakthrough. An early campaign poll put the NDP's Janis Irwin well ahead of Conservative Kerry Diotte and Liberal Brian Gold.
Surrey-Newton: The NDP's Jinny Simms is trying to hold off a charge from former Liberal incumbent Sukh Dhaliwal. Meanwhile, Conservative candidate Tory Harpeet Singh is turning it into a three-way race because he is a well-known local broadcaster.
Vancouver South: Conservative Wai Young is being challenged by Liberal star candidate Lt.-Col. Harjit Singh Saggan, the first Sikh to command an army regiment in the Canadian Forces. The NDP is fielding Amandeep Nijja, a national labour union staffer.
Vancouver-Granville: This new riding, carved out of several Vancouver voting districts, is being closely watched. There's lots of speculation about the role of strategic voting in the riding as Conservative Erinn Broshko, Liberal Jody Wilson-Raybould and the NDP's Mira Oreck face off in a tight race.
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