SANTIAGO, Chile — Chileans faced a stark choice between left and right on Sunday as they began voting in a presidential election that has the potential to make or break the effort to draft a new constitution.
The race was the nation’s most polarizing and acrimonious in recent history, presenting Chileans with sharply different visions on a range of issues, including the role of the state in the economy, pension reform, the rights of historically marginalized groups and public safety.
José Antonio Kast, 55, a far-right former lawmaker who has promised to crack down on crime and civil unrest, faces Gabriel Boric, 35, a leftist legislator who proposes raising taxes to combat entrenched inequality.
The stakes are higher than in most recent presidential contests because Chile is at a critical political crossroads. The incoming president stands to profoundly shape the effort to replace Chile’s Constitution, imposed in 1980 when the country was under military rule. Chileans voted overwhelmingly last year to draft a new one.
campaigned vigorously against establishing a constitutional convention, whose members Chileans elected in May. The body is tasked with drafting a new charter that voters will approve or reject in a direct vote next September.
Members of the convention see Mr. Kast’s rise as an existential threat to their work, fearing he could marshal the resources and the bully pulpit of the presidency to persuade voters to reject the revised constitution.
“There’s so much at stake,” said Patricia Politzer, a member of the convention from Santiago. “The president has enormous power and he could use the full backing of the state to campaign against the new constitution.”
Recent polls have suggested Mr. Boric has a slight edge, although Mr. Kast won the most votes during the first round of voting last month.
Mr. Boric has referred to his rival as a fascist and has assailed several of his plans, which include expanding the prison system and empowering the security forces to more forcefully crack down on Indigenous challenges to land rights in the south of the country.
Mr. Kast has told voters a Boric presidency would destroy the foundation that has made Chile’s economy one of the best performing in the region and would likely put the nation on a path toward becoming a failed state like Venezuela.