Majority government for Mark Carney could hinge on one Quebec riding

The Terrebonne seat was annulled by the Supreme Court after a one-vote result and is now one of three upcoming byelections that could bring the Liberals to 172 seats if they win all three.

The Terrebonne federal seat near Montreal is vacant after the Supreme Court of Canada annulled last year’s one-vote result. The decision followed a complaint about a mail-in ballot that was returned because Elections Canada’s envelope had the wrong address. The vacancy is one of three seats set for byelections that could affect whether Prime Minister Mark Carney’s Liberals reach a majority. Key facts: - Tatiana Auguste was declared the winner by one vote after recounts in the last election; the result was later annulled by the Supreme Court. - The annulment followed a report that a Bloc voter’s mail-in ballot was returned due to an incorrect address on the Elections Canada envelope. - With Conservative MP Matt Jeneroux’s recent floor crossing to the Liberals, a sweep of the three byelections would give the governing party 172 seats, the bare minimum for a majority. - Terrebonne is described by analysts as a francophone, suburban riding where the Bloc usually performs well and which is not considered a safe Liberal seat. - The two Toronto ridings that will also hold byelections are seen as long-held Liberal seats; the Liberals have named candidates in those contests while some other parties have yet to finalize nominees. Summary: The outcome in Terrebonne could directly affect whether the Liberals achieve a House majority, given the narrow margins and recent floor crossing. Terrebonne cannot be called before Feb. 27, which makes April 6 the earliest possible election date for that riding, while the timing of the Toronto byelections remains at the prime minister’s discretion. Undetermined at this time is whether additional floor crossings or another vacancy will alter the arithmetic before the byelections occur.