Patrick Long on Saturday expanded his lead in the SCCA Pirelli World Challenge GT championship with a win at Infineon Raceway in Sonoma, Calif., while Peter Cunningham extended his career-win tally in the GTS category, and Lawson Aschenbach collected his fourth Touring Class victory of the year.

Johnny O'Connell's No. 3 Cadillac Racing CTS-V took the pole position, with Long's No. 45 Porsche 911 GT3 lining up alongside. But Randy Pobst split the duo at the start of the race to take the lead.

Pobst led in his K-Pax Racing Volvo S60 until electrical issues forced him to pit on lap four. Long took over the lead and never looked back, finishing 5.053 seconds ahead of O'Connell in the 27-lap, 60.615-mile race.

"There's three rounds to go, and points are very close," Long said. "World Challenge rewards you for laps led, leading a lap and qualifying as well, so you really have to put a complete weekend together."

O'Connell scored his fourth podium in five races with his second-place finish.

"I was struggling, fighting the rear of the car from the third lap on," O'Connell said. "I kept hoping that [Long] would have [issues with] tires, but he didn't. Then I was hoping he would hit traffic, and he didn't, and then I was hoping I could hang on. All things considered, as difficult a race car as it was, second is a good result."

Mike Skeen started sixth in his No. 2 Chevrolet Corvette but fought his way up to a third-place finish.

"We had a big hiccup in qualifying and threw it away," Skeen said. "I think we had a good car then and should have been at least top three. We got a decent start and got lucky in traffic and got around Andy [Pilgrim]. I feel kind of lucky to be on the podium today, but we'll take it."

Long extended his GT drivers' championship lead to 124 points over O'Connell.

The GTS class saw Cunningham start on pole in his No. 1 Acura RealTime Racing TSX. But the Ford Mustangs of Eric Foss and Paul Brown were able to move past Cunningham at the start, dropping him to third place.

Foss's No. 73 Traxxas/St. Jude/SPX Ford Mustang FR500S led for the first lap until Brown made a move in his No. 50 Ford Mustang Boss 302S. Cunningham passed Foss on lap eight and set his sights on Brown. He moved into the lead on lap 18 when Brown slid wide at the exit of turn seven. Cunningham crossed the finish line with a 4.989-second lead over Brown for his 41st career win.

"It feels great. World Challenge is even more competitive than ever this year," Cunningham said. "Last year, GTS had some growth to do as a new class, and since the start of the 2011 season, it's been really competitive--so competitive that our car hasn't been on the top step. The Acura has been good all year, just not quite as good as the higher-horsepower, bigger-displacement cars. But the RealTime Racing guys kept working hard, trying to make sure that we had the best weapon to use out there, and a track like Sonoma is definitely a good track for the Acura."

Brown finished in second, followed by the No. 16 Red Line Oil Ford Mustang Boss 302S of Greg Liefooghe in his World Challenge debut.

Aschenbach led every lap in the Touring Car class to earn his fourth win of the year. He started from pole in his No. 71 Compass360 Racing Honda Civic Si but was hounded by Aaron Povoledo's No. 88 K-Pax Racing Volvo C30. Aschenbach cruised to the win after Povoledo's Volvo experienced a mechanical failure on lap three.

"We obviously had a very good points day today," Aschenbach said. "The minute Povoledo fell out, it was pretty much points, take care of the car, and keep it on the track. Fortunately, this track suits the Civic very well. Hats off to the Compass360 guys and Honda HPD for making it happen. It was a great car and a great track for us, and we're really happy to take the win."

Tristan Herbert came home 8.826 seconds behind Aschenbach to secure second place in his No. 33 Volkswagen GTI. Patrick Seguin's No. 80 Honda Civic Si rounded out the top three.