Jim Clark kept alive his chance of snatching the world championship from Graham Hill with a determined win in the United States Grand Prix.
For the third consecutive year, Ferrari did not make the trip across the Atlantic. After a miserable season without a victory, they were near the bottom of the constructors' table, having won it in 1961, and had been completely outclassed by the new British V8 engines. After shattering the lap record in practice, Clark was on pole, with Richie Ginther and Graham Hill in BRMs alongside him. On a damp and misty day, he got a great start and led in the early stages, with Hill hot on his tail. On the 12th lap, Hill nipped past as Clark negotiated some back markers, but five laps later Clark was back in front and stayed there for the remainder of the race.
However, it wasn't all plain sailing for Clark as he drove his Lotus without a clutch for the second half of the race. It failed after 50 laps, so he had to change gear 'by ear', which he managed to do brilliantly to keep Hill at bay.
Ginther, in third, began to struggle with a deteriorating gear box and fell back through the field until his engine blew after 35 laps. That left Bruce McLaren and Dan Gurney battling for third, and McLaren made sure of the place when Gurney began losing power on lap 58. Jack Brabham, in only his second grand prix driving his Brabham Climax, came home fourth to register the first championship points for his self-designed car.
Clark eventually won by 17 seconds from Hill and said afterwards; "I planned to get in front and stay there. I set up the car for dry weather just before we started. I sure am glad the weather held up!" He was lucky, as shortly after he took the chequered flag it started to rain.
The championship was perfectly poised going into the final race in South Africa, with Hill on 39 points and Clark on 30. Clark could be champion if he won the race, as, although they would be equal on 39 points with only the best five results counting, he had more outright wins than Hill.