After 12 years leading the Liberal Party of Canada, Prime Minister Justin Trudeau on Monday said he was stepping down. His resignation sets off a succession battle in which some of the party’s most prominent faces will vie to replace him.

In Canada’s political system, the leader of the Liberal Party, as the head of the largest party in the House of Commons, is also prime minister; when Mr. Trudeau’s replacement as party leader is chosen, they will assume the position as well.

That politician will take the party to general elections to face the Conservatives and their leader, Pierre Poilievre, who are dominating public opinion polls. Elections must be held no later than October, but the government, under its new prime minister, is expected to fall long before then through a vote in the House of Commons.

Mr. Trudeau said the Liberal Party would choose his successor through a vote by its members, a relatively small portion of Canada’s population. While no one has yet announced their candidacy to succeed Mr. Trudeau, here are some possible contenders.

Chrystia Freeland

The resignation last month of Chrystia Freeland, the former deputy prime minister and finance minister, incited widespread speculation that she would start her own bid to run the Liberal Party.

Ms. Freeland had a successful career in Canada as a senior editor at The Globe and Mail in Toronto and as an international journalist working as a correspondent and newsroom leader for the Financial Times and Reuters. Ms. Freeland, who was born and raised in Alberta, returned to Canada to join Mr. Trudeau’s Liberals in 2013. She is married to a reporter on the Culture desk of The New York Times.