The family dynasties expected to dominate political discussion worldwide this year are named Bush and Clinton. But another potent political dynasty is making news in Canada, where on Monday, Justin Trudeau, son of former Prime Minister Pierre Elliott Trudeau, led the center-left Liberal Party to a decisive victory over Prime Minister Stephen Harper’s Conservative Party. The win could signal a shift not just in Canadian politics, but in the U.S.-Canada relationship as well.

The 11-week campaign was twice as long as most in Canada, but a sprint compared with America’s slog. Canada’s economy, sclerotic since extraction industries aren’t giving back as much, was the top issue. With that backdrop, Trudeau’s pledge of three years of deficit spending on infrastructure proved popular. The country’s economy would also get a boost if Canada, the U.S. and 10 other nations implement the Trans-Pacific Partnership trade pact. Trudeau cautioned that he needed the full text of the agreement before committing, but he has consistently voiced his support for free trade. Minnesota would likely benefit from an economic recovery in Canada, the state’s top export market.

Politically, Trudeau’s support for the XL Keystone pipeline may not square with President Obama’s indecision on the issue, but other policy shifts may mesh better with the president’s agenda, including a more open approach to combating climate change than Harper. Stylistically, the 43-year old Trudeau will likely better connect with Obama. But he has also pledged to end Canada’s participation in the U.S.-led bombing mission against the Islamic State of Iraq and the Levant. And legalization of marijuana, a Liberal Party position, might impact the debate in the U.S.

As in the U.S., immigration was a contentious issue in the Canadian campaign. Harper was hurt by being seen as less flexible, which matters in a cosmopolitan Canada that has a higher percentage of foreign-born citizens than America. And Harper’s emphasis on Muslim women covering their faces during citizenship ceremonies was eventually, and rightly, dismissed as divisive politics.

Trudeau’s triumph is a stunning turnabout for the Liberals, who were routed by both the Conservatives and the left-leaning New Democratic Party in the last election.

“Justin Trudeau will continue in the great tradition not just of his father, but the Liberal Party,” Mike Medeiros, a postdoctoral researcher at the Centre for the Study of Democratic Citizenship at McGill University in Montreal, told an editorial writer. “But it’s not your father’s Liberal Party, and not his father’s Liberal Party. As his father revolutionized Canada, the next four years will revolutionize Canada. … It’s a victory for change.”

In Ottawa, yes, but also in Washington, where bilateral relations are sure to reflect Canada’s sharp political turn.