Evo Morales' bid to extend his presidency by amending the constitution heads toward a narrow defeat, according to a referendum's early results released Monday morning.
Morales has governed Bolivia for a decade and is seeking a fourth term starting in 2019.
The referendum's timing could not have been worse for Morales, the country's first indigenous president. He was stung this month by an influence-peddling scandal involving a former lover and by a deadly incident of political violence.
Two unofficial "quick counts" by polling firms that looked at counts from a sampling of polling stations said 52 percent voted "no." One firm, Ipsos-Apoyo, said it saw ballots at one of every 15 polling stations.
Official vote counting was slow. With just 23 percent polling stations reporting just after midnight, the "no" vote stood at 67 percent. But vote reports were particularly slow in coming from the countryside, where Morales is most popular. State television halted election coverage shortly before midnight.
A frustrated Vice President Alvaro Garcia said at a news conference Sunday night that the vote was so far "a technical tie" — too close to call.
"No one has won, nor has anyone lost," he said. Morales did not make an appearance.
Michael Shifter, president of the Inter-American Dialogue think tank in Washington, called the tight vote a surprising, major blow to Morales, who tallied more than 60 percent in his 2014 re-election.
"While few can deny that Bolivia has seen impressive economic growth and social progress under Morales' rule, many voters are sending a message that it is not enough — they are demanding clean government, accountability and more competitive politics," Shifter said.
Morales, who entered politics as a coca growers union leader, could now be motivated to groom a successor, he added.
Bolivia's constitution, enacted in Morales' initial term, permits presidents and vice presidents to serve two consecutive terms. Morales' first term was deemed by a high court not to have counted.
International observers reported only minor irregularities in Sunday's vote.
The referendum followed by days a political bombshell: A former lover of Morales was named sales manager of a Chinese company in 2013 that has obtained nearly $500 million in mostly no-bid state contracts. Morales denied any impropriety and his claim to have last seen the woman in 2007 was questioned when a picture of them together last year emerged.
The case deepened doubts about the integrity of Morales' governing Movement Toward Socialism, which has been wracked by scandals.
Adding to Morales' woes, six city workers died of smoke inhalation last week in El Alto, the teeming city adjacent to the capital of La Paz, in an attack blamed on pro-Morales agitators. The attackers torched documents that allegedly incriminated the previous mayor in payroll corruption.
Both developments blighted Morales' achievements in cutting poverty, spreading Bolivia's natural resource wealth and empowering its indigenous majority during a decade in office.
Eusebio Condori, a retired schoolteacher, said he voted "no" because the scandal and the deaths "confirm that this government doesn't have a plan for Bolivia, only for itself."
A mother of three, Maria Espinoza, said she voted "no" because she believes in term limits. She echoed the complaint of others that too many jobs depend on political patronage.
South America's left has recently been sullied by scandal — and punished at the ballot box in Argentina and Venezuela — but Morales had personally remained unscathed.
His movement has been discredited, however, by the skimming of millions from the government-managed Fondo Indigena, which runs agricultural and public works in the countryside.
Morales presided over an unprecedented economic boom as prices for raw materials soared just as he took office.
He built airports, highways and the pride of La Paz, an Austrian-built aerial tramway system. He also put a Chinese-built satellite into space. Average per capita income rose from $873 to $3,119 and a new indigenous middle class was born.
But the boom is over. Bolivia's revenues from natural gas and minerals, making up three-fourths of its exports, were down 32 percent last year.
Economists say Morales leaned heavily on extractive industries to pay for populist programs and failed to diversify the economy.
In addition, judicial corruption has been endemic and press freedom suffered as major news outlets were purchased by people friendly to the government. Critical media and environmentalists complained of harassment by the state.
Based on reporting by the Associated Press.