Tony Stewart’s day isn’t a washout; he wins Fontana NASCAR race

Ninety minutes before Sunday’s NASCAR race, with sunshine still peeking through the growing clouds, Auto Club Speedway President Gillian Zucker was asked about the rainstorm bearing down on the Fontana track.

Ever the optimist, Zucker said, “I’m extremely confident we’ll get the race in today.”

She was right, barely. With Tony Stewart leading, the Auto Club 400 had just crossed the halfway point — and become an official race — when steady rain arrived and the rest of the race was washed out.

So Stewart, the reigning Sprint Cup Series champion, collected his second win in five races this season, the other coming in Las Vegas.

Stewart appeared set to take his No. 14 Chevrolet to Victory Lane even if the race hadn’t been called by NASCAR after 129 laps and instead had gone its full 200 laps.

“Whether it rained or didn’t rain, I felt confident we had a car that . . . had a great shot at winning,” said Stewart, 40, who co-owns his Stewart-Haas Racing team.

Indeed, although Kyle Busch led 80 laps in his Toyota, Stewart twice ran Busch down on the two-mile Fontana oval to take the lead in front of a crowd NASCAR estimated at 90,000.

“Stewart was way faster and he was really good in traffic,” Busch said after finishing second.

Dale Earnhardt Jr. was third, 2011 race winner Kevin Harvick fourth and Carl Edwards was fifth.

Greg Biffle, Edwards’ teammate at Roush Fenway Racing, finished sixth and stayed atop the season standings by seven points over Harvick and 17 over Earnhardt.

Stewart, who’s racing contrary to his history of starting slowly each season, is fourth in the standings, 18 points behind Biffle.

It was the first Cup race shortened by rain at Auto Club Speedway since the track, originally named California Speedway, staged its first one in 1997.

The rain’s arrival also caused unexpected finishes for at least two other drivers, Denny Hamlin and five-time champion Jimmie Johnson.

Hamlin, Busch’s teammate at Joe Gibbs Racing and the pole-sitter, still was running in the top three when the only caution period of the day — for the start of the rain showers — brought out the first yellow flag.

While Stewart, Busch and most others stayed on the track to avoid losing positions as the rain set in, Hamlin’s crew brought his No. 11 Toyota to pit road for tires and fuel. He came out 11th and, as the rain intensified, that’s where he finished.

Johnson, Earnhardt’s teammate at Hendrick Motorsports and the only five-time winner at Fontana, also pitted and shortly after he returned to the track, his Chevrolet developed an oil leak.

So the rain was good fortune for Johnson, who finished 10th. Had the race resumed, Johnson’s crew would have been forced to fix the leak, costing Johnson several more spots.

The lack of yellow flags was a factor in the race’s becoming official. Two or three caution periods might have prevented the drivers from reaching the halfway point before the heavy rain arrived.

Everyone knew the rain was coming, so there was an urgency for the drivers to reach the front in case the race was shortened.

Asked how he approached the day, Busch replied, “Whoever is leading after halfway, if the rains get here right in time, you’ll be the winner.”

But Stewart’s crew chief, Steve Addington, said Stewart told him just before the race that “I won’t mention [the rain] until you do” and simply focused on gaining the lead.

Stewart, a three-time Cup champion, credited Addington for his 46th Cup win.

“Every time [Addington] changed something, the car really responded well to it,” Stewart said. “Each run we got better and better.”

james.peltz@latimes.com