Left-wing politicians from across the Western Hemisphere gathered in Uruguay this past weekend to lick their wounds from a string of election losses and strategize on how to counter growing aggression from the Trump administration.

There were ex-presidents and expected presidential contenders, national lawmakers and campaign strategists, best-selling authors and protest leaders. But perhaps the toast of the weekend — viewed by the group as the inspiration for a path forward — were the democratic socialists from the United States, fresh off their primary victories.

Those candidates — Darializa Avila Chevalier and Claire Valdez of New York, Chris Rabb of Pennsylvania and Dr. Adam Hamawy of New Jersey — were all special guests at the Panamerican Congress in Montevideo, an annual meeting of leftist political leaders from across the Americas. (Dr. Hamawy identifies as progressive but not democratic socialist.)

They received a standing ovation, were asked for selfies and were repeatedly cited by fellow attendees as examples on how the left can succeed in the current political moment.

Their victories “give us hope that if this can be fought from within, it can also be fought from the outside,” said Gabriel Boric, the former president of Chile, who was succeeded in March by a hard-right politician aligned with President Trump.

Mr. Boric, 40, a former protest leader, said the left had been failing to make the case to the working class that it was best positioned to help them, but the democratic socialists in the United States were showing they could.

“There is a tendency in our movement to constantly talk about the right and all the evils it represents, instead of convincing and giving hope to the people,” he said in an interview. “Now that debate is happening in the United States.”

The warm welcome for the primary winners was a sign of how, even on the international stage, many people frustrated by the march of the global right are pinning their hopes on the progressive wing of the Democratic Party despite its limited success.

It was the first official foreign trip for the progressive candidates since they won their primaries. (All are safe bets to win congressional seats, so campaigning has slowed.)

The trip signaled their interest in Latin America amid the Trump administration’s pressure campaign in the region. Yet, in interviews, they declined to speak with much substance about Latin America, aside from calling for an end to the U.S. trade embargo on Cuba. They all had focused almost exclusively on Gaza as a foreign policy issue in their campaigns, and they said the trip was educational for them. That also meant they appeared uneasy with the idea that other attendees were looking to them as teachers.

“I don’t think we’re really telling them anything; it’s a conversation and listening,” said Dr. Hamawy, a former U.S. Army veteran who served in Iraq. “They do see a little hope in at least the United States is not a monolith, and they see that there are partners in the U.S. who have a better view of the future.”

The left in Latin America will take any help it can get. Right-wing candidates have won all seven of the region’s presidential elections since Mr. Trump took office, and those leaders and others have worked to align their governments with the Trump administration.

The U.S. government also captured the leftist autocrat Nicolás Maduro in Venezuela and has exerted control over the country while pressuring the Communist government in Cuba with an oil blockade that has led to widespread suffering for the nation.

The remaining leftist governments are in Brazil, Mexico, Uruguay and Nicaragua, which is run by an authoritarian government. Brazilians will vote in October whether to swing to the right, and Mexico has strengthened its ties with the Trump administration.

Ms. Avila Chevalier, who is expected to win the district that represents parts of Harlem and the Bronx, said that the region’s leftists might be able to learn from democratic socialists’ efforts to build a movement against the odds.

“We’re building an infrastructure for progressive movements almost from the ground up,” she said. “We won because we built a campaign rooted in building a coalition, building people power and making sure that we were actually responding to what people need.”

David Adler, an American activist who organized the meetings, said that Latin America had often inspired leftist movements in the United States, but the reverse was now happening.

“For the first time in my life, I feel like there’s actually a lot that the United States — and recent experiences that we’ve had in this primary season in particular — can teach our friends here in the south,” he said. He cited messages about affordability that were working with voters.

The U.S. delegation at the event was largely from the progressive wing of the Democratic Party. Also present were the foreign policy advisers of Senator Bernie Sanders and Mayor Zohran Mamdani of New York, as well as Representatives Jesus Garcia of Illinois and Pramila Jayapal of Washington.

Ms. Jayapal, who is on the House Foreign Affairs Committee, said that if Democrats were in control, they would seek to investigate the Trump administration’s moves toward Cuba and Venezuela, as well as its airstrikes on boats it says are carrying drugs.

“I’ve been collecting a lot of ideas through this conference about different places where we would want to weigh in,” she said.