By Luciana Magalhaes and Ricardo Brito
SAO PAULO, July 24 (Reuters) - Argentine President Javier Milei flies to Brazil on Friday to throw his weight behind Senator Flavio Bolsonaro's presidential run at a party convention, hoping to extend a regional wave of right-wing electoral wins to Latin America's biggest country.
The rare endorsement of a foreign head of state at the nominating convention offers Bolsonaro's campaign a fresh jolt of energy after months of scandal and infighting. The son of former President Jair Bolsonaro has slipped behind President Luiz Inacio Lula da Silva in the polls.
Other conservative parties have avoided backing Bolsonaro's run while his father serves a prison sentence under house arrest for a failed coup plot. The imported star power may help the senator consolidate a fractured field.
"Having Milei at the convention helps energize and mobilize the party's more ideological base," said Silvio Cascione, Eurasia Group's head of Brazil, noting the alignment with recent right-wing victories in Colombia, Peru, and Chile.
"INTERNAL EROSION"
The Bolsonaro campaign is ready for a reboot after months of headwinds. In May, the senator confirmed reports that a banker since jailed in a major fraud and bribery investigation provided him with funding to produce a film about his father's political career. Fresh scrutiny emerged this week after federal police received authorization to investigate the financing.
Last month, a public spat with his stepmother threatened his standing with women voters. This week, new U.S. tariffs on Brazilian goods put fresh focus on his family's mixed results courting intervention from U.S. President Donald Trump.
Surveys by pollster Quaest have shown that Bolsonaro now has a deficit of eight percentage points in a potential second-round runoff against Lula, whereas he held a technical lead in April.
"Flavio's campaign is facing internal erosion," said political analyst Rafael Favetti. The elder Bolsonaro, who has shown no sign of leaving politics for good, continues to wield influence through his wife, Michelle Bolsonaro, and others, weakening Flavio’s position as the natural heir to the Bolsonaro brand, the analyst added.
As of late on Thursday, a press officer for the senator had not replied to a request for comment.
RIGHT-WING WAVE
The endorsement of Milei, whose 2023 victory in Argentina began a wave of nearly a dozen Latin American elections won by candidates aligned with Trump, is a reminder of the wider tailwinds giving Bolsonaro a chance.
Across the region, concerns about crime and economic stagnation have boosted conservatives with a broadly shared agenda of "order first, markets second, and a closer relationship with Washington," JPMorgan told clients this week.
The Argentine leader will travel next to Peru for the July 28 inauguration of Keiko Fujimori, to Ecuador for talks with conservative President Daniel Noboa and to Colombia for the August 7 inauguration of right-winger Abelardo de la Espriella.
Flavio Bolsonaro's agenda so far has much in common with their winning law-and-order platforms.
On crime, he has proposed lowering the age of criminal responsibility to 16 from 18 and building new maximum-security prisons, inspired by El Salvador's President Nayib Bukele.
On the economy, he vows tax cuts and privatizations to forge a leaner government, while criticizing Lula for food inflation, which has dented the president's popularity.
"MORE CENTERED"
However, the bigger question hanging over Bolsonaro's campaign is how to inherit his father's fervent supporters while establishing a broader appeal to Brazilians tired of a decade of intensely polarized politics.
In December, after his father backed his run, effectively sidelining the popular Sao Paulo Governor Tarcisio de Freitas, the senator tried to define himself in terms of moderation.
"I consider myself, truly, a more centered Bolsonaro," he told Reuters in an interview at his Brasilia office in December.
He has made trips to Europe, the Middle East and Washington, where he met with Trump and Secretary of State Marco Rubio, playing up the notion of a global conservative alliance on the rise.
But missteps at home have left potential allies on the sidelines and emboldened conservative challengers still polling in the low single digits. Pundits still project a hard-fought runoff between Lula and Bolsonaro in October, but for now the momentum has swung to the incumbent.
"These elections depend on Lula slipping on a banana peel," said Brasilia-based Favetti.
(Reporting by Luciana Magalhaes in Sao Paulo and Ricardo Brito in BrasiliaAdditional repoting by Lucila Sigal in Buenos AiresEditing by Brad Haynes and David Gregorio)
