While the 22-year-old Briton celebrated his fourth victory of an extraordinary debut season, his closest rival and double world champion team Fernando Alonso crashed out of an action-packed and rain swept race.
The result left Hamilton in a position to clinch the championship in Shanghai next weekend. He now has a 12-point advantage over Alonso with only the Chinese and Brazilian Grands Prix remaining.
However, he was fortunate to escape without damage from a collision with Poland's Robert Kubica that sent both drivers spinning off.
"I was very fortunate that I finished," said Hamilton, who led the first 19 laps behind the safety car with others struggling in the spray behind him.
"It was the longest race probably of my life. It just seemed to go on and on."
Renault rookie Heikki Kovalainen was second, for his and the outgoing world champions' first appearance on the podium this year, with fellow-Finn Kimi Raikkonen fighting from last to third for Ferrari to stay at least mathematically in the title reckoning.
Hamilton has 107 points, Alonso 95 and Raikkonen 90.
Raikkonen's team mate, Felipe Massa, saw his slim championship hopes killed off when the Brazilian finished a fighting sixth after making four pitstops to Hamilton's one.
Massa, who battled side-by-side through the spray with BMW Sauber's Kubica through the final corners, with each pushing the other wide before the Brazilian finally prevailed, is now 27 points adrift of Hamilton.
Both Ferrari drivers paid the price for errors and a disastrous initial tyre choice, lining up on intermediates when the race started behind the safety car and then having to pit for extreme wets.
While Ferrari's interest in the drivers' championship faded away, with McLaren almost certain of their first title since Mika Hakkinen in 1999, they at least had the consolation of a constructors' title won off the track.
McLaren were stripped of all their points and fined $100 million earlier this month for a spying controversy.
Alonso crashed 27 laps from the end while in fifth place after his car had been damaged in a collision with Toro Rosso's Sebastian Vettel.
With debris strewn over the track and the wrecked McLaren left stranded, the safety car was again deployed.
Briton David Coulthard was fourth for Red Bull after Australian team mate Mark Webber and Vettel collided during that safety car period while in a stunning second and third place respectively.
Vettel, in only his sixth race, had led for three laps and was distraught with his mishap.
Italian Giancarlo Fisichella was fifth for Renault, Massa sixth, Kubica seventh and Italian Vitantonio Liuzzi scored Toro Rosso's first point of the season in eighth.