Chile’s right wing have claimed a jubilant victory after José Antonio Kast, a former congressman with a history of defending the Pinochet dictatorship, secured a surprise win in the first round of the country’s presidential election.

Kast, who campaigned on a platform of public order, migration controls and conservative social values, confounded expectations to take 28% of the vote and beat the progressive former student leader Gabriel Boric by two percentage points.

The two will face off in a second-round repechage on 19 December.

“I would like to thank God and my family,” Kast announced to rapturous applause on Sunday night in a leafy square in one of Santiago’s wealthiest neighbourhoods. “Chile deserves peace and freedom – and that’s what we’re going to give you.”

Across town in a middle-class barrio lined with bars and restaurants, Boric expressed confidence that “hope will triumph over fear”.

But the result is a bracing reality check for the Chilean left after two years in which the country has followed a broadly progressive trajectory.

Since 2019, mass anti-inequality protests have rocked the country, leading to the election of a broadly leftwing assembly to rewrite Chile’s Pinochet-era constitution.

But Sunday’s result suggested that the protest movement’s ability to galvanise support has worn thin.

Kast survived a bruising final week of campaigning in which his open support for Genl Augusto Pinochet’s dictatorship and its economic legacy were the subject of intense scrutiny.

As he took to the brightly lit stage on Sunday night, he had regained some of the composure that had deserted him before the vote, presenting the runoff election as an existential fight against “the intransigent left”.

“We are going to chose between freedom and communism – between democracy and communism,” he said.

Kast’s campaign spokesperson, Macarena Santelices – a great-niece of Gen Pinochet who briefly served outgoing President Sebastián Piñera as women’s minister – also appeared on stage.

Supporters – some wearing Make America Great Again caps, others with the Chilean flag draped around their shoulders – joined in chants hailing “liberty” and mocking the crowds who gathered in 2019.

Later, some stopped to cheer officers from the Carabineros national police force, which was accused of torture, cover-ups and a litany of human rights abuses during the protests.

Throughout the campaign Kast has managed to project his short, simple messages on TikTok to a younger generation of voters far more efficiently than his competitors.

And his vision for Chile has found a solid foil in Gabriel Boric, a former student protest leader who has served two terms in congress since being elected in 2013.

Boric’s agenda is feminist, green and progressive, but his strong support among young, middle-class, university-educated Chileans in Santiago appears not to have seeped into other demographics.

“It looks like some of the things Boric stands for don’t respond to people’s urgent needs,” says Valentina Rosas, a political scientist at Chile’s Pontifical Catholic University. “They have no bearing on the price of bread or stopping people breaking into your home.”

Abstention is a persistent feature of Chilean elections – where rarely more than half of the electorate turns out. Despite the seemingly high stakes of yesterday’s election, participation hit just 47%.

An important factor in next month’s runoff will be the votes of those who backed the libertarian businessman Franco Parisi in the first round. Parisi did not set foot in Chile during the campaigns owing to a child support dispute with his ex-wife, but defied expectations to take 13% of the vote.

The destination of Parisi’s share of the vote, which largely comprised young, lower-middle-class men from outside the capital according to one early study, is likely to prove pivotal in the second round.

The more moderate centre and centre-right candidates Yasna Provoste and Sebastián Sichel took 12% of the vote apiece.

“My fear for the second round is that this turns into an election based on fear. People might end up voting against certain policies, rather than in favour of what they actually want,” says Rosas.