During the presidential campaign, Bolsonaro announced that he would not accept the election results unless he won. The highly charged campaign has also led to divisions between family and friends thanks to two dramatically different candidates, Jair Bolsonaro and Fernando Haddad, facing off in the last round.
The runner-up has vowed to "defend freedoms" of president-elect's opponents.
"We can not continue flirting with socialism, communism, populism and the extremism of the left", he said in a speech transmitted live on Facebook - the platform he has campaigned on since an attacker stabbed him in the stomach at a rally on September 6, putting him in the hospital for three weeks.
And from Jan 1, he will be Brazil's new President.
In Brazil, far-right candidate Jair Bolsonaro won a sweeping victory in a presidential runoff election on Sunday, marking the most radical political shift in the country since military rule ended more than 30 years ago. The people have spoken. "For the first time I feel represented", said Andre Luiz Lobo, 38, a businessman who - not incidentally, given the accusations of racism against his candidate - is black.
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If it can't, and that goes for all the companies listed above, it could leave investors quite disappointed down the road. Tesla's stock , which rose 5.2% Friday during official trading, was down 1.8% in after-hours trading.
In celebration, Mr Bolsonaro's supporters set off fireworks on Rio de Janeiro's famous Copacabana Beach. "We are going to change the destiny of Brazil", he said, in an acceptance address, promising to root out graft and stem a tide of violent crime.
Opponents have warned Bolsonaro would try to veer toward authoritarianism, after he openly expressed his admiration for Brazil's brutal military dictatorship (1964-1985) and its torture of leftist dissidents.
Former Brazilian President Dilma Rousseff after voting at a polling station in Belo Horizonte, Brazil.
The former army captain has commented that he would rather his sons die than come out as gay, and told a female politician that she "wasn't worth raping".
Popular anti-corruption judge, Joaquim Barbosa, who jailed several top PT leaders for corruption, also came out for Haddad. Lula himself is serving a 12-year prison term. "Brazil owes a lot to former President Lula".
The victor, who presented himself as "anti-system" despite being a legislator since 1991, is controversial for his insults to women, blacks and homosexuals, and for his praise of torture and the last Brazilian dictatorship (1964-1985).
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The statement, calling the journalist's death "tragic", says the two presidents had a telephone call on Sunday, without providing more details.
But the election also revealed that the historical divisions between Brazil's northern and southern regions remains significant, with the relatively poor north-east (which supported Haddad) establishing itself as a left-wing bastion.
These are uncertain times, with many anxious that - with Mr Bolsonaro in power - the gains made in Brazil since the country returned to democracy 30 years ago could be erased.
Haddad narrowed Bolsonaro's lead to 8 percentage points in an Ibope poll released late Saturday, a survey that gave him 46 percent compared with Bolsonaro's 54 percent.
In Sao Paulo, the economic capital, Marcos Kotait, 40, a publicist, said he had "never seen such a polarized election". Election officials expected about half of all registered voters living overseas in MetroWest to cast a ballot Sunday - low compared to turnout in Brazil, where voting is compulsory for all literate citizens between the ages of 18 and 70, but high compared to participation in past elections by Brazilian expatriates, Benvenuti said.
"Tomorrow we start a new country", said Mario Marcondes, a 61-year-old pilot who gathered with other supporters outside Bolsonaro's house.
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The U.S. acknowledges China's stance but provides Taiwan with defense equipment and opposes reunification by force. The U.S. has also accused China of engaging in cyberattacks against the U.S. government and businesses.