Front-runner Mark Carney and underdog Chrystia Freeland, both established, centrist policymakers, are vying to succeed Justin Trudeau amid grave threats to Canada from the United States.

Canada's ruling Liberal Party elected a new party leader Sunday who will serve as the nation's next prime minister, replacing outgoing premier Justin Trudeau. Why it matters: Liberal Party members' vote for Mark Carney comes as the Liberal Party is experiencing a polling boost amid widespread opposition to President Trump's policies targeting its northern neighbor.

Frontrunners include Chrystia Freeland and Mark Carney, who are making the case they can guide Canada through domestic and international issues. At the top of the list: mounting trade tensions with the United States.