OTTAWA — Prime Minister Mark Carney’s Liberals won a federal election Monday, the country’s public broadcaster, the CBC, projected, an extraordinary comeback that was fueled in part by President Donald Trump’s tariff policies and attacks on Canada.

Just months ago, Carney’s party was headed for a potentially historic drubbing. It was not yet clear whether the Liberals would rule a minority or majority government as votes continued to be counted. This is the fourth consecutive Liberal government since 2015.

Amid the U.S. president’s trade war and threats to annex its northern neighbor, voters flocked to Carney — a political novice, who led the Bank of Canada during the global financial crisis and the Bank of England during Brexit. He pitched himself as a steady hand at a destabilizing time.

The vote, considered by many here to be the most consequential election of their lifetimes, was bookended by Trump’s menaces. During the first week of the campaign, he announced tariffs on foreign automobiles, prompting Canadian retaliation. On Monday morning, in a social media post, Trump wished “good luck” to Canadians and repeated his threat to make their country the 51st state.

The result represented a remarkable reversal in fortunes for the Liberals, who were all but written off when Justin Trudeau resigned as prime minister in January. They had trailed the Conservatives for more than a year. Pierre Poilievre, a sharp-tongued populist, was cruising to one of the largest majority governments in Canada’s history.

But Trudeau’s exit, Carney’s elevation as his replacement and Trump’s return flipped the script. By the time Carney called a snap election in March, the Conservatives had lost a 20-plus-point lead. Poilievre, who built his edge on the premise that Canada is “broken” thanks to Trudeau, struggled after his main foe was out of the picture — and Trump-induced Canadian patriotism surged.

The shift in public opinion, analysts said, was seismic.

“To say it’s unprecedented is not only an understatement,” said Lori Williams, a political scientist at Mount Royal University, “it underplays the magnitude of the shift.”

The outcome could raise questions about Poilievre’s leadership and the future of the Conservatives, who have lost four consecutive elections. Its leaders have struggled to unite the party’s factions and to expand the base. Before the vote, recriminations from prominent Conservatives about Poilievre’s campaign had spilled into public view.

Canada, which sends nearly 80 percent of its exports to the United States, has been a repeated target of Trump’s tariffs. The Bank of Canada said this month that a prolonged global trade war could tip the economy into a recession. Already, the levies and broader trade uncertainty are weighing on business and consumer confidence here.

The country’s economy has long been stagnating. Grocery costs are straining budgets. For younger Canadians, the prospect of homeownership feels increasingly out of reach. There are also regional divisions, particularly over natural resource development, that could complicate efforts to make the country more resilient in the face of Trump’s threats.

Analysts said that the campaign was dominated by dueling, but also interlinked, ballot questions: Who could best stand up to Trump and manage the fallout of a rupture in U.S.-Canada ties and who could best deliver change. Voters, they said, focused less on policy and more on the leadership styles of the front-runners.

Carney, 60, a former Goldman Sachs banker who has been prime minister for less than two months, pitched himself as the candidate best able to steer Canada through Trump’s tumult. He had some stumbles during his first foray into elected politics, but voters were willing to stomach them, judging the president’s threats a bigger issue and Carney’s bland competence an antidote to Trump’s chaos.

“I have managed crises before,” Carney said at a campaign rally on the weekend. “This is a time for experience, not experiments.”

Carney has said that he will seek a new trade and security relationship with the U.S. He backs targeted retaliatory tariffs and has said Canada will meet its NATO defense spending commitments by 2030 at the latest. While certain sectors of the economy will remain integrated with the U.S., he has pledged to diversify Canada’s trading relationships with “reliable” partners.

Canada’s “old relationship with the United States, based on deepening integration of our economies and tight security and military cooperation, is over,” Carney declared last month.

To voters hungry for change, he presented himself as the antidote to Trudeau. On his first day as prime minister, he moved to slough off the political baggage of his predecessor by canceling Trudeau’s controversial consumer carbon tax.

Poilievre, 45, a career politician and brash attack dog, had long hammered Trudeau over his economic record, pointing to the carbon tax as one reason life was more unaffordable. But once the prime minister and his carbon levy were out of the picture, he struggled to pivot off his “ax the tax” message in a contest that was no longer a referendum on the former prime minister.

“I know you want to be running against Justin Trudeau,” Carney told Poilievre in a leaders’ debate this month. “Justin Trudeau isn’t here.”

The Conservative leader sought to cast Carney as an out-of-touch elitist who was “just like Justin.” He charged that electing a Liberal government under Carney would continue many of Trudeau’s policies and that he was the only leader who truly represented change. He pledged to cut taxes and red tape, to get tough on crime and to build pipelines.

“We cannot afford a fourth Liberal term,” Poilievre said at a campaign rally last weekend. “We need a change.”

Poilievre also appeared flat-footed in the face of Trump’s broadsides, in part because some of his base supports the president. Some in his party had called for him to shift his campaign’s focus to Trump. He blamed a “lost Liberal decade” for leaving Canada vulnerable to Trump’s threats, but he continued to emphasize concerns around affordability.

Poilievre’s penchant for sloganeering and use of insulting nicknames for opponents also made him appear unserious at a moment of crisis, analysts said. His promises to slash foreign aid and the federal public service, vows to eradicate a “woke culture” from the military and pledge to eliminate public funding for “woke” university research reminded voters too much of Trump, they said.

In the last week of the campaign, the Conservatives ran ads that did not feature Poilievre — a sign, analysts said, that his brash and pugilistic style was turning off key parts of the electorate. Many left-of-center voters who might ordinarily cast ballots for the New Democratic Party or the Bloc Québécois gravitated toward the Liberals to stave off a Conservative win.

Voters do not directly vote for the prime minister. Instead, voters in 343 electoral districts, or ridings, elect a member of Parliament to represent them in the House of Commons.