Given Trump's track record of throwing his weight behind his Latin American allies -- like Argentine leader Javier Milei, Colombia's presidential hopeful Abelardo de la Espriella and Nasry Asfura in Honduras, to name but a few -- a similar intervention in Brazil appears likely.
"It can be expected that Brazil will also be the target of a US attempt to influence the elections" given Trump's past "partisan interventionism," according to Oliver Stuenkel, a professor at the Getulio Vargas Foundation.
The US leader's influence could be less clear-cut this time around, however.
While celebrating his "excellent chemistry" with leftist President Luiz Inacio Lula da Silva, who is seeking reelection, Trump has also called candidate Flavio Bolsonaro, the son of former far-right president Jair Bolsonaro, a "smart young man who loves his country."
Both have visited the White House in recent weeks.
Lula, who has accused Trump of behaving like an "emperor," praised their solid rapport after the pair's meeting in May.
But within days of Bolsonaro's visit the same month, Trump endorsed a cause celebre of Brazil's political right by designating the country's two largest drug cartels as terrorist organizations.
He also announced possible tariff hikes on Brazilian products, much to the displeasure of the Lula administration.
- 'Decisive factor' -
With polls currently projecting a tight second round between Lula and Bolsonaro, the right-wing camp is adamant that victory requires a healthy relationship with Washington.
Bolsonaro took to social media to celebrate his own role in getting Trump to designate the so-called Red Command (CV) and First Capital Command (PCC) crime groups as terrorist organizations.
"On a trip as a pre-candidate, we did more for Brazil and the safety of Brazilians than the Workers' Party and Lula did in 17 years in office," he boasted.
Tens of millions of Brazilians living in working-class areas are highly concerned by organized crime and the violence it generates.
"The US measure benefits Flavio and wears down Lula, who has always been against it," pro-Bolsonaro lawmaker Sostenes Cavalcante told AFP.
Cavalcante views the American leader as a "decisive factor" in the campaign, but said the Trump card must be used prudently.
"We must be very careful, because he has a positive side that benefits us but also a high disapproval rating," he said, alluding to polls showing that Brazilians are divided over the US president.
- 'Trump-Lula channel' -
Despite enormous ideological differences, Lula has managed to keep Trump on his side -- but only sometimes.
Washington's decision to slap sky-high tariffs on Brazil in 2025 as retaliation for convicting Jair Bolsonaro of plotting a coup marked a sour patch in the pair's relations.
Most of those tariffs have since disappeared, but the recent proposal to impose 25 percent tariffs on some Brazilian products for alleged unfair trade practices has once again rankled Brasilia.
Lula blamed the increased tariffs on Bolsonaro's whisperings in Washington, calling the right-wing candidate a "traitor" to his own export-reliant country.
Although Bolsonaro denies the allegation, "the tariffs canceled out the advantage Flavio had gained from the US decision regarding the PCC and the CV," said Stuenkel.
Lula is attempting to negotiate directly with Trump but says he is being blocked by US Secretary of State Marco Rubio, a Cuban-American whom the leftist has called a "mortal enemy" of Latin America.
Nevertheless, "the Trump-Lula channel is the best thing" the US-Brazil relationship currently has, Bruna Santos, Brazil director at the Inter-American Dialogue think tank, told AFP.
"Their last meeting is what calmed tempers," she said.
Both leaders have confirmed their attendance at the G7 summit in France from June 15 to 17, but it remains unknown if they will meet one-on-one during the event.
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