MILLVILLE - It's hard enough driving a racecar at high speeds around a road course with 14 turns. It's even harder in pouring rain.

NASCAR's three top series do not race in the rain. Neither does IndyCar. Their races are often postponed, delayed in mid-race or shortened due to wet track conditions.

But a little rain doesn't stop the Grand-Am Rolex series from racing.

Sunday's Verizon Wireless 250 at New Jersey Motorsports Park went on as planned despite rain that started about two hours before the start and continued throughout. Ricardo Zonta and Nic Jonsson won the race, finishing more than 44 seconds ahead of second-place Max Angelelli and Brian Frisselle.

It wasn't easy. The Rolex cars have special rain tires, but that doesn't completely offset the slick conditions. And there's not much that can be done about visibility when rain is both pouring down and splashing up as 31 cars race around the track.

"You can't see anything out there," said John Pew, who along with Michael Valiante finished 11th in Sunday's race. "It's a complete white-out. I couldn't even see the brake markers out there."

The race got off to an ominous start. Last year's winner, Mark Patterson, wrecked with Ricky Taylor on the first turn of the first lap. The first five laps were consequently run under caution.

"(I was thinking), 'OK, here we go,' " said Leh Keen, who along with Dirk Werner finished first in the slower GT class (eighth overall). "You have no idea what's going to happen. Really, you can only judge the car that's closest to you that you can see."

Patterson said he tried to do too much considering the conditions.

"At the start, I passed (two cars), and I should have just left it at that," he said. "You could just not see anything out there."

There ended up being only three more cautions. But cars slid off the track throughout the race, putting many of the track's new tire walls to good use.

"In these conditions it's really up to the driver to hold the car on the track, which is the most important thing," Werner said.

It made for exciting racing. Every turn was even more of an adventure than usual.

"Racing in the rain is one of the joys of sports-car racing," said Dave Spitzer, Grand-Am's vice president of competition. "We love it. I think the teams enjoy the challenge, and the drivers enjoy the challenge. It's a badge of honor for everybody involved."

The fans appreciated it, too. They knew as soon as the rain started that it would make for more interesting racing.

"Is there any bright spot to the way the weather is? Yes, there is. The fact that there are real racers out here that aren't afraid to run in it," said Joe McGinley of Wall Township, taking a not-so-subtle shot at the Sprint Cup.

Jonsson said he actually does better in the rain. He embraced the challenge.

"Coming out of the front straightaway was tough when it was raining hard," said Jonsson, who drove the winning car along with Zonta. "Also, going into Turn 3, there was a big puddle there. So there were a few places on the track, but for the most part it was OK."

There is a point when the rain can become too much even for Grand-Am, though. Even the rain tires can't compensate when water is pooling on the track.

That happened Sunday on Lap 32, about an hour into the two-hour, 45-minute race, and the caution flag came out. It lasted about 30 minutes.

"When they start to hydroplane on the straightaway, they can't put the power to the ground and it becomes dangerous beyond any normal measure," Spitzer said. "We know that there's a very fine line between, 'Hey, we're having fun, this is sport,' and, 'Hey, this is dangerous beyond measure.' "

Eventually the rain let up slightly, though, and that was all it took to get back to racing. The track had installed more drainage at various spots in the offseason.

"It worked amazingly well," NJMP general manager Kevin Wittman said.

The rain led to some quirky problems for a few drivers.

Reigning series champions Scott Pruett and Memo Rojas were leading the race early on, before their windshield wiper malfunctioned. The pit crew couldn't initially fix it, and Rojas drove with no functioning wiper until the next pit stop. They lost valuable time and finished 21st.

"This whole windshield wiper drama just killed us," Pruett said. "Surprisingly, the conditions weren't really that bad - if you could see. Without the wipers working, you couldn't see anything out there."

Several other drivers had issues with their windshields fogging up. Jon Fogarty's pit crew rigged up a makeshift solution, wrapping cloth around a pipe for him to use to wipe the windshield from the inside.

A surprising number of fans attended the race despite the rain. The track does not release attendance figures, but most of the grandstands were filled and there appeared to be more spectators than there were last season, the track's first.

"My impression is that under the conditions it was a remarkable showing by hearty race fans," Wittman said.

Notes: Actor Patrick Dempsey finished seventh in the GT class. … David Donohue, a Malvern, Pa., resident who vacations in Cape May, finished fourth overall. … Romain Dumas and Timo Bernhard, who started on the pole, were third. … Summit resident Bryce Miller finished ninth in GT.

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