TRENTON, Canada

The Liberal Party membership will elect a new leader and prime minister-designate Sunday from a field of four candidates.

The new prime minister will inherit a country that could be on the road to economic disaster if US President Donald Trump follows through with his 25% tariffs on imported Canadian goods. It is arguably the worst crisis Canada has faced since World War II.

Prime Minister Justin Trudeau, facing rebellious party members who saw the ruling Liberal government and Trudeau plummeting in public polls, announced he would stay on until the party voted in a new leader, then walk away after winning three elections over 10 years.

The news the deeply-unpopular Trudeau was leaving resulted in a dramatic rebound in public polls. They rebounded and cut deeply into the double-digit lead that was enjoyed by the opposition Conservative Party.

Who are the runners?

The person selected to replace Trudeau as Liberal leader will become prime minister after a brief transition of power. That, in turn, will result in a federal election upon a no-confidence vote in the House of Commons, and that could come any day after March 9.

The leader will be chosen from a field that includes the former head of the Bank of Canada Mark Carney; former Deputy Prime Minister Chrystia Freeland; ex-Cabinet minister Karina Gould and Frank Baylis, a former Member of Parliament.

The polls suggest Carney, who has never entered politics, is the front-runner.

Who is voting?

People who have registered as Liberals can vote. Voting is done online and in fact, about 400,000 people had signed up to vote as of Jan. 30. Voting closes at 3 p.m. Eastern Time (1900GMT) Sunday.

There are 343 Liberal ridings (districts) across the breadth of Canada and each candidate is awarded points based on the number of votes received.

If no one receives more than 50% of the overall points on the first ballot, the one who received the least number is eliminated. That person’s points are then distributed to the other candidates based on their performance in each riding.

The winner will be announced later Sunday.

Trump and his tariff-inducing trade war will be the number one priority