Nayib Bukele, a former mayor of El Salvador’s capital, has won a landslide victory in Sunday’s presidential election, winning more votes than his two closest rivals combined to end a quarter of a century of two-party dominance in the crime-plagued Central America nation.

The supreme electoral court declared Bukele the winner, saying he had nearly 54% of the votes, with nearly 90% of ballots counted. Carlos Callejas of the Nationalist Republican Alliance was far behind in second with less than 32%, while even farther back were former foreign minister Hugo Martinez of the Farabundo Marti National Liberation Front (FMLN) and a minor party candidate.

Bukele surpassed the 50% threshold to avoid a March runoff, and he had already claimed victory before a jubilant crowd in San Salvador and invited supporters to celebrate in the streets.

“We have full certainty that we have won the presidency, and we have won in the first round,” Bukele said.

He stood on an anti-corruption platform and campaigned on the slogan: “There’s enough money when no one steals.”

All four candidates had promised to end corruption, stamp out gang violence and create more jobs, with crushing crime at the top of the agenda. About 67,000 Salvadorans belong to gangs that terrorise their communities with extortion, murder and other forms of violence.

The candidates proposed creating economic opportunities and restoring social values to dissuade Salvadorans from engaging in criminal behaviour.

There were no reports of major problems in voting.

Bukele, 37, made his political debut in 2012 as a small-town mayor with the now-ruling FMLN and won election in the capital three years later, automatically making him a potential presidential contender. But his frequent criticism of the leftist party’s leadership led to his expulsion, and he wound up as the unlikely standard-bearer of a small conservative party known as the Grand Alliance for National Unity, whose initials –Gana – mean “win” in Spanish.

The FMLN and the conservative Alliance, known as Arena, have dominated Salvadoran politics since a 1992 peace deal which ended a brutal civil war. But both parties have been stained by corruption scandals and neither has been able to stem gang violence.

Voter Estela Henriquez, 27, said outside a polling station in the capital: “I came to vote because I want the country to change, because we are tired of so much corruption.”

More than 4,500 election observers, including representatives of the Organization of American States and the European Union, were on hand.

El Salvador is small both in size and population, with just 6.5 million people. Close to a third of its households live in poverty, while the World Bank says per capita income is $3,560.

Salvadorans searching for a better life have joined recent caravans of migrants trekking through Mexico toward the US.