The final grand prix of an astonishing and controversial season, in a city as crazy about motor racing as Italians are about Ferrari, has all the elements of a three-way thriller.
McLaren's Hamilton, the 22-year-old Briton who has been the revelation of the year whatever happens at Interlagos, can become the first rookie champion in 58 years and also the youngest.
Formula One's first black driver has 107 points, four more than his estranged Spanish team mate and double world champion Alonso.
Alonso can join a select band of triple champions as well as becoming the first driver since the late Argentine Juan Manuel Fangio in 1957 to win back-to-back titles with different teams.
Three points behind Alonso is Ferrari's Raikkonen, who has won more races than the other two but has also paid the price for his team's comparative unreliability.
If the unflappable Finn were to add the drivers' title to Ferrari's constructors' crown, it would be a remarkable fightback for a man who was 17 points adrift of Hamilton with two races remaining.
LESSON LEARNED
Formula One has seen nothing like it since the Australian Grand Prix of 1986, the last time that three drivers entered the final race of the season vying for the title.
"Motor racing and Formula One has never been more popular than it is just now," said Britain's triple champion Jackie Stewart, a big fan of Hamilton's. "We've had a better season than we've ever had."
Raikkonen and Alonso will be going all out to win while Hamilton can afford a more strategic approach, knowing that third or even fourth place could be all he requires at an unfamiliar and tricky anti-clockwise circuit.
The youngster has learnt his lesson from the last race in China, where he might have wrapped up the title had he not skidded into a gravel trap at the pit lane entry.
"China was another valuable lesson for me this season, and an incident I will take from and try to develop as a driver," Hamilton said in a team preview.
"I moved on from the disappointment pretty quickly and since leaving Shanghai, my sole focus has been on Brazil," added the Briton, whose boyhood idol Ayrton Senna was born and buried in Sao Paulo.
"Whilst I might be ahead by four points, this Championship is still very open. I will do what I can to score the points I need, and the rest is out of our hands," he added.
While Hamilton must be considered the favourite, and will revive local fans' memories of Senna with his similar yellow helmet, Alonso won both of his titles in Brazil and has experience on his side.
The Spaniard will also have a special scrutineer appointed by the governing body to make sure, despite McLaren's oft-repeated policy of driver equality, that Hamilton receives no special treatment from the British team.
"We can categorically state that they will be given the exact same opportunity to win the race and the Championship," said McLaren chief executive Martin Whitmarsh.