SÃO PAULO—For years Jair Bolsonaro was a bizarre sideshow in Brazilian politics—an outlandish ex-army captain who waxed nostalgic about the dictatorship he served and only got one bill enacted in nearly three decades as a congressman.
Now, the 63-year-old stands on the verge of winning Brazil’s presidency, after taking 46% of Sunday’s first-round vote in a crowded field, some 17 percentage points ahead of the second-place finisher and his rival in an Oct. 28 runoff, leftist Fernando Haddad.
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