(Reuters) - International leaders celebrated the overwhelming victory on Sunday of Guatemalan presidential aspirant Bernardo Arevalo, a win which had long seemed out of reach for the anti-graft candidate in an elections process shaken by accusations of government intervention.
"A salute to the people and government of Guatemala for an exemplary election day, a true civic celebration," said Organization of American States (OAS) chief Luis Almagro on X, the social media network formerly known as Twitter.
Arevalo, a 64-year-old former diplomat and son of Guatemala's first democratically elected president, nabbed 58% of votes versus former first lady Sandra Torres' 37%, with nearly all votes counted late Sunday.
"The outcome of the vote is already very clear," European Union's foreign policy chief Josep Borrell said in a statement. "It is crucial for all state institutions and all sectors of society to support and join in this effort in the interests of the country."
Arevalo, who ran on a campaign of fighting corruption, faced an uphill battle at the polls. He came in a surprise second place in a first-round vote earlier this year, triggering a run-off. A number of other opposition candidates had been barred from running.
His competitor Torres alleged irregularities in the first round of voting and Arevalo's party, Semilla, was briefly suspended at the request of a top prosecutor.
By Monday morning, Torres had yet to accept her loss publicly. In a press conference Sunday afternoon, the candidate, an ally to outgoing President Alejandro Giammattei, said she was "worried" about the integrity of the vote.
Her UNE party said in a statement late Sunday it would take a position once the elections results were put out "with total transparency."
An OAS representative, with a team of 86 election observers in Guatemala, said voting had gone smoothly and the election "fulfilled all the demanding obligations."
An EU mission will put out a preliminary statement with its findings on Tuesday.
The EU, as well as governments such as Brazil and Norway said they expected a peaceful transition of power.
However, the attacks on Arevalo are likely to continue, said Risa Grais-Targow, analyst at political risk consultancy firm Eurasia Group.
"The ruling pact will likely continue to target electoral officials and Arevalo's Semilla party with investigations ahead of January's change in government," she said.
President Giammattei has vowed to ensure an orderly transition of power. He said on X he had congratulated Arevalo, and invited him to meet "the day after election results were finalized."
Arevalo will face challenges once in office, as Guatemala is roiled by violence and food insecurity. Guatemalans now represent the largest number of Central Americans seeking to enter the United States.
Arevalo said he had already spoken with Mexican President Andres Manuel Lopez Obrador and Salvadoran President Nayib Bukele on Guatemala's agenda with its neighbors.
Honduran President Xiomara Castro said on X she was sure that following Arevalo's win, "We will unify the people of Central America."
(Reporting by Kylie Madry; Editing by Chizu Nomiyama)