Faster Hamilton optimistic but cautious ahead of Brazil
Speaking at a circuit where he has won three times, the seven-time world champion said he was focussed on ensuring Mercedes finish second behind Red Bull in the constructors' championship and then build a car to match the runaway leaders next year.
"I really don't know," he said when asked if he can win Sunday's race, after crossing the line a strong second behind champion Max Verstappen in Texas, where he was disqualified after a car inspection, and Mexico.
"After the last couple of races, people message me and say 'ah, it's looking good' but it was looking good at the end of last year too, and we started 1.5 seconds behind at the start of the year!
"I'm not dazzled by where we are currently. I'm happy and I'm proud. The only reason I was on the podium is the great work that has gone on in the background.
"I'm more thinking quite long-term at the moment and short-term, just trying to solidify second in the constructors' because that's so important for everyone in the team, but I anticipate that Red Bull is going to blitz it because their car has been great.
"But, if that's not the case, I'll be ready to take the fight to them. If it can be anything like Austin and we can get the strategy better, it would be incredible."
In Mexico, Hamilton turned sixth on the grid into second.
As he seeks his first win for 700 days on Sunday, he added: "I came away empty-handed last season... I don't plan on that this year."
A strong result for Hamilton would also enhance his chances of finishing runner-up to Verstappen in the drivers' title race.
With three races remaining, Hamilton is only 20 points adrift of Sergio Perez in the second Red Bull.
Verstappen has made clear that does not plan to assist Perez on Sunday, saying the Mexican does not need team orders to help him.
"At the end of the day, it should not matter," he said.
"I'm confident in Sergio, that he can stay ahead. On average, we have had the fastest car this season so let's hope we don't get into that situation."