Bolivia’s President Evo Morales has said he is still hopeful he can win a referendum which would allow him to stand for a fourth term in office.
With 82% of the votes counted, those opposed to the proposed constitutional amendment were leading by 8.4 percentage points.
Mr Morales said the votes were still trickling in from the countryside, where he enjoys greater support.
Observers said count was slow but that there was no evidence of fraud.
Mr Morales, Bolivia’s first head of state of indigenous origin, said he would respect the result of Sunday’s referendum but accused right-wing sectors of waging a “dirty war”.
An indigenous Aymara and former coca leaf producer, he took office in January 2006, and his current term ends in 2020.
The constitutional change would allow Mr Morales to run for re-election in 2019 and potentially remain in power until 2025.
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The president urged all groups to have “serenity and responsibility” while they wait for the official results, and said he was “optimistic” that the votes from rural areas would give him a boost.
“They do not like us much in the city,” he told a press conference on Monday.
Officials have not said when the final official results will be announced.
Pollsters suggested a victory for the “No” camp based on unofficial quick counts, prompting celebrations by “No” campaigners in various Bolivian cities.
Mr Morales is still a popular leader and the economy has grown steadily over the past decade.
But many – specially in the main cities – think Mr Morales should not be allowed to serve 19 consecutive years as president, analysts say.
Opposition leader Samuel Doria Medina urged Mr Morales to “recognise the results” and focus on solving Bolivia’s problems in his remaining time in office instead of trying to run for another term.
Evo Morales in office
- First elected president in 2005: Began by renationalising the country’s oil and gas industries and boosting social spending. Won a referendum in August 2008 on whether he should stay in office, and then a few months later a referendum approved his plans for a new constitution
- Re-elected in 2009: His second term followed a landslide win, and Mr Morales continued to pursue left-wing policies
- Again re-elected in 2014: He was able to run again despite the 2009 constitution limiting presidents to two consecutive terms in office. The Constitutional Court ruled his first term should not count because it had not taken place under the new constitution. His current terms ends in 2020
- Another run in 2019? A win in Sunday’s referendum would let him stand again, and potentially serve until 2025
‘Life will go on’
Mr Morales also said that “life will go on” if he loses his bid.
“With my record, I can leave happily and go home content. I would love to be a sports trainer,” he was quoted as saying in an interview (in Spanish) with the Spanish newspaper El Pais.
Observers say there is no clear successor to him if he fails in the referendum, and that the opposition lacks a single leader.
Despite a drop in the international price of oil and natural gas, the Bolivian economy has performed well in the past 10 years, growing on average 5% a year.
The government’s socialist policies have also been successful in reducing extreme poverty.
But recent allegations that Mr Morales used his influence to favour a Chinese construction firm in Bolivia have damaged his approval ratings.
A former girlfriend of Mr Morales, Gabriela Zapata, holds an important position in the company, CAMC, which has secured more than $500m (£350m) in contracts with the Bolivian government.
Mr Morales rejected the allegations and said he had nothing to hide. He ordered an investigation into how the contracts were awarded.