Sunday, October 04, 2026

Is Bolsonaro Brazil's Condorcet Winner?

Condorcet winners seem like an optimist's dream - but finding Condorcet winners in elections is like trying to find a four leaf clover. But could there be one in the Brazil presidential election? Brazil runs its elections as majority rule with a runoff, so since no candidate reached 50% or more of the vote after the recent election results, Lula (incumbent) and Flávio Bolsonaro will be sent to a runoff election. Many of the candidates that received less than 3% of the vote are right of center, so Lula would likely not be the Condorcet winner since Bolsonaro is very right-wing. But does Bolsonaro have the makings of a Condorcet winner? 

There one way this is likely to go when comparing Bolsonaro with any of the minor candidates, including Cury. In an election between Bolsonaro and Cury, if all 47% of Bolsonaro's voters vote for him again, the 53% of other voters decides the election results. Bolsonaro would win the election if he gets a share of non-Bolsonaro voters such that: 47 +53*s > 50 =. s > 3/53=5.7%. Cury would need a share of 94.3% of all non-Bolsonaro voters to win, so it seems like Bolsonaro is a shoe-in for a Condorcet winner. 

To prevent Bolsonaro from becoming a Condorcet winner, 94.3% of all non-Bolsonaro voters would need to vote for Cury. Even though Lula's base is very anti-Bolsonaro, a 90%+ preference for Cury from all non-Bolsonaro voters seems unlikely. Strategic voting could have also caused understatements in the minor candidates' first-round support, which may mean that some Bolsonaro voters engaged in strategic voting and did not vote for Cury even though they liked him. With all that in mind, it still seems like this is a likely case where Bolsonaro is an elusive Condorcet winner.

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