Driving a Ford-Cosworth/Lola, Tracy was fastest at 121.220 miles per hour, covering the 2 1/4-mile Sports Car Course in 1 minute, 7.058 seconds.
After earning a championship point Friday for his provisional pole, he picked up another valuable point to pull within one of
Bruno Junqueira, who supplanted him atop the standings last week.
It was the fifth pole of the season and 18th career for Tracy, who had been leading the standings virtually the entire season until Junqueira won last week's Mario Andretti Grand Prix.
Rookie Ryan Hunter-Reay will start second in a Ford-Cosworth/Reynard after clocking 121.192 mph in 1:07.074 on his ninth lap.