The Social Liberal Party candidate, Mr Bolsonaro has received support from former Trump White House adviser Steve Bannon who backed the “great leader” for the victory.
He said: ”Captain Bolsonaro is a Brazilian patriot, and I believe a great leader for his country at this historic moment.
“The populist movement is a global phenomenon.
“The trend is definitely in our favour and that’s why I think Bolsonaro will win big.”
Since leaving the White House Mr Bannon has supported the far-right movement across Europe and now in South America, Trump’s former advisor has compared his movement to that of the US President.
He said: “He’s a figure like Trump. It was the 2008 financial crisis that lit the fuse that exploded with Donald Trump’s candidacy and his presidency. Brazil is going through that type of crisis now.”
Like Mr Trump, the seven-term congressman, Bolsonaro, 63, has successfully pitched himself as the anti-establishment candidate, appealing to voters fed up with political state and the rise in violent crime.
On 7 October, in the first round of the presidential election, far-right candidate Mr Bolsonaro obtained an impressive 46.03 percent of the votes cast, or one-third of the registered voters.
However his rival Haddad, 55 dismissed the result and backed his party to win.
The Workers Party’s candidate wrote on Twitter: “I have some news for you… Bolsonaro said last Sunday that he was going to sweep away the opposition.
“Well, he’s not going to have an opposition because he will not be governing. We’re going to win this.”
Although the right-wing candidate appears to hold the lead in the polls his lead has appeared to be falling by as much as 6 percent in recent weeks.
Mauro Paulino, the head of Datafolha polling institute, said: “It’s impossible to say if there will be a continuous migration of votes (from Bolsonaro to Haddad) that would continue until the election on Sunday.”
This is something that has infuriated Mr Bolsonaro who dismissed the legitimacy of the polls, his campaign has argued they are fraudulent and favouring leftist candidates.
Mr Bolsonaro said: “Our lead is far bigger.”
However it appears Mr Bolsonaro may be taking notice of his lead slipping after softening his stance, on Thursday unlike Trump, he made the surprise call to not pull out of the Paris climate agreement, if elected, after previously stating he would.
The second round election votes takes place on Sunday.