2021 Canadian federal election (Mackay as CPC leader)

The 2021 Canadian federal election was held on September 20, 2021, to elect members of the House of Commons to the 44th Canadian Parliament. The writs of election were issued by Governor General Mary Simon on August 15, 2021, when Prime Minister Justin Trudeau requested the dissolution of parliament for a snap election.

Trudeau failed to win his third term as prime minister, the original goal of this early election. Though the Liberals were hoping to win a majority government to govern alone, the results backfired for them. The Liberals won the second most seats at 139; as this fell short of the 170 seats needed for a majority in the House of Commons. The Liberals set a record for the lowest vote share of a party that would go down in history, winning 32.7 percent of the popular vote, while losing the popular vote to the Conservatives as they did in 2019.

The Conservatives led by Peter MacKay won 141 seats, greater than the seats they made in 2019 obviously, and were finally able to form a (minority) government since they lost in 2015 with the confidence of Bloc Québécois (CAQ influence). The Bloc Québécois led by Yves-François Blanchet won 31 seats, losing one seat compared to the last election. The New Democratic Party led by Jagmeet Singh won 25 seats, a net increase of one seat, but nonetheless fell short of expectations. The Green Party maintained two seats but party leader Annamie Paul was defeated for the third time in her riding of Toronto Centre. The party received 2.3 percent of the popular vote, approximately a third of what they won in 2019. The People's Party did not win any seats, despite winning nearly 5 percent of the popular vote, and party leader Maxime Bernier was defeated for the second time in his riding of Beauce.

Following the election, Paul resigned as Green Party leader two months after the election. Although Liberals were able to get the confidence of the NDP but Bloc Québécois decided they will support a MacKay-led Conservative government (164 < 172). Hence, Trudeau resigned in October 2022 after failing to get Bloc Québécois' support to form a minority government. In March 2022, the BQ formed a confidence and supply agreement with the Conservatives.