Why President Bolsonaro is warring with his own party

Until 2018, few people, if any, had ever heard of the Social Liberal Party (PSL). Between 1998—the year of its foundation—and 2014, the party won only four congressional seats, never grabbing more than one per electoral cycle. In 2006, when the party put forward its first ever presidential candidate, it received 62,064 votes—only 0.06 percent of valid ballots. But in 2018, the PSL was elevated to the second-largest party in Brazil’s lower house, with a total of 53 seats and only one behind the Workers’ Party, one of Brazil’s very few grassroots political parties.

The reason for this mercurial rise? The presidential campaign of PSL member Jair Bolsonaro.

But almost exactly a year after the party’s biggest political win, the PSL is on the verge of implosion, amid a struggle for control over the massive resources the party will receive from a publicly-financed campaign fund ahead of Brazil’s municipal elections next year. Some of the PSL’s highest-profile members are under investigation, suspected of operating a scheme of dummy candidates to siphon money from the aforementioned campaign fund. And President Bolsonaro has publicly discussed leaving the party.

It is safe to say that without Mr. Bolsonaro, the PSL would continue being a “dwarf” party in Brazil’s political system. But it is also true that without the PSL, Jair Bolsonaro might never have been elected president. In 2018, most small right-wing parties were keen on allying themselves with then-São Paulo Governor Geraldo Alckmin. The idea of launching the candidacy of a traditional backbencher to the presidency was too rogue for Mr. Bolsonaro’s previous home, the Social Christian Party, hence his move to the PSL.

Now, relations have bittered between party chairman Luciano Bivar and the president, creating a schism in the biggest conservative force in the country. Both sides accuse the other of corruption, calling for investigations....