Morales, leader of the Movement to Socialism (MAS) gained 47.07 percent of the nation's popular vote, enough to put him 10 percentage points above his closest rival, Carlos Mesa who gained 36.51 percent of votes. A final, official proclamation by the TSE is still pending.
The incumbent had won with 53.72 percent in 2005, in 2009 with 64.22 percent and in 2014 with 63.36 percent of the ballots.
Bolivia's electoral law requires 50 or more of the votes plus one for a candidate to be declared winner, or 40 points with a 10 percent advantage. Morales is declared president during the first round of elections, making a second round unnecessary.
El @GobiernoMX felicita al Presidente del Estado Plurinacional de #Bolivia@evoespueblo por su victoria y le deseamos el mayor de los éxitos en su próxima gestión, saludando fraternalmente al hermano pueblo boliviano. ��������
@GovernmentMX congratulates the President of the Plurinational State of #Bolivia @evoespueblo for his victory and we wish him the greatest success in his next term, fraternal greetings to the Bolivian people.
There have been clashes between defenders and detractors of Morales with security forces in regions such as Santa Cruz and Cochabamba all this week as tensions have risen since the ballots were cast Oct. 20.
After an almost final vote count that gave him a sufficient advantage to avoid a second round, Morales said that the election observation mission of the Organization of American States (OAS) slandered him by raising what he called "serious doubts" about the official count and impartiality of Sunday's election.
The OAS local team on Thursday recommended that Bolivia convene a second round after an unexpected interruption of vote counting and a sudden change of trend in favor of Morales , which led to protests and accusations of manipulation by the opposition.
"The OAS mission is already in a coup d'etat," Evo said during a press conference, in which he again accused his main rival, also former president Carlos Mesa, of trying to steal his victory.
"It is an internal and external coup d'etat. The OAS as a whole should evaluate ... the mission that has come," he added.
The OAS mission in Bolivia declined to comment to Reuters.
In third place is the Presbyterian pastor of Korean origin Chi Hyun Chung, of the Christian Democratic Party who took away 8.78 percent of the vote.