Hamilton and team-mate Jenson Button have effectively thrown in the towel on their personal hopes of glory, trailing Sebastian Vettel by 62 and 84 points respectively, with only 100 now available.
McLaren have fallen to third in the constructors' championship, 83 points adrift of Red Bull with a potential 172 to aim for after a run which has seen the Woking-based team bring both cars home just twice in the last seven races.
Hamilton cannot even draw on his bitter experience of 2007, when he held a 17-point lead going into the final two races - when 10 was the maximum for a win - only to lose out by a point.
"I was 17 points ahead going into those last two rounds in 2007. How many points is 17 worth today? 40 or so?" said Hamilton.
"It's a much bigger gap now, and back then it took a lot of bad luck for me to lose the title.
"Sebastian doesn't have that kind of bad luck - ever - and Fernando (Alonso) is driving fantastic, so I don't think it's the case I can win it.
"The gap is not especially easy to close up, but it's not impossible
"If Jenson and I were able to deliver the constructors' title, even without a drivers' title, that would be a fantastic way to end the season."
Remarkably, McLaren have not won the constructors' crown since 1998, and it would be a fitting way for Hamilton to end his career with them.
The 27-year-old will bid a fond farewell to the team at the end of the campaign, ending his 14-year association before joining Mercedes on a three-year, £15million-per-season contract.
Although Hamilton addressed 600 Vodafone guests last Friday at the McLaren factory, he has yet to stand up in front of the workforce.
"We haven't planned anything as such yet," said Hamilton.
"In Suzuka I had planned a dinner with the team, but that didn't come off, so at some stage we'll do that before the end of the season.
"Once the season is done and I am on my way out of the door then I definitely will meet everyone in the canteen (at the factory) and have a chat, open up the floor if they want to ask questions.
"But the season is not over yet. We're still fighting together, so to say goodbye right now would be silly because they need me and I need them, for us to work together to win this championship."
Following Friday's two practice sessions ahead of Sunday's Indian Grand Prix, it appears Hamilton and Button are steeling themselves to again trail in Vettel's wake.
The two Britons were just under a second off the pace of Vettel, who was quickest in both 90-minute outings at the Buddh International Circuit.
Assessing his hopes for the weekend, Hamilton said: "In qualifying (pace) we aren't quick enough, which I hope is to do with fuel load.
"I'm hoping they were looking to improve their qualifying runs and they were on lighter fuel, if not, then we're in trouble.
"But it should be quite a close race because our race pace is not so bad compared to others.
"But to beat the Red Bulls we need to really try to change something, and gain something with the downforce.
"They are just too quick, and Ferrari are quick. Right now we're only quick enough to be third or fourth."
As for Button, the 32-year-old suffered a gearshift problem on the second lap of his long run, bringing his second session to an early conclusion.
On the gap to Red Bull, Button admitted: "It is massive.
"On low fuel, yes, and on high fuel it is probably about three or four-tenths (of a second).
"It's not good and we need to work on it. I don't think we're going to claw back the qualifying pace, but race pace is possible.
"It's still going to be very difficult to chase them, with qualifying more difficult. For the race we're still a lot closer, but a long way behind."
Only Vettel's Red Bull team-mate Mark Webber could keep pace, the Australian just over a tenth of a second adrift.
Ferrari's Fernando Alonso, six points behind Vettel who has won the last three races, found himself six-tenths of a second down in third such was the difference between the Red Bulls and the rest.