NEWTON, Iowa — Most people think of their 30th birthday as a milestone to forget. Dan Wheldon spent his in victory lane.

Wheldon turned the big 3-0 in style today, winning the Iowa Corn Indy 250 for his second victory of the season. Wheldon plans to donate his winnings to the victims of Iowa's recent floods and tornados.

"What a great day for Target Chip Ganassi Racing and a great birthday present for me," Wheldon said.

Indeed it was — especially after Wheldon's risky decision not to pit for the final 90 laps paid off.

Wheldon took the lead out of a caution flag 60 laps from the finish while almost every other driver took a pit stop. Wheldon guessed correctly that his old tires would do the trick, and he then held off Andretti Green drivers Hideki Mutoh and Marco Andretti down the stretch.

The Ganassi duo of Wheldon and Scott Dixon have five victories in nine IRL races this season. Wheldon's last victory came in Kansas in April.

"My car was just so loose with new tires," Wheldon said. "Staying out was important. I had good restarts on the older tires."

Mutoh, the current rookie leader, picked up his career-best finish by crossing the line in second. The Tokyo native earned a ride with Andretti Green after finishing second in the IndyPro points race in 2007, and he keeps getting better.

Mutoh has finished seventh or better in four of his last five races.

"I am very happy to finish second," Mutoh said. "I am almost there, so maybe next time."

Andretti pulled off his best finish since also placing third in the Indy 500.

The first 190 laps were essentially a duel between Tony Kanaan and Helio Castroneves, both IRL veterans in search of their first win of the season. But that all changed when Enrique Bernoldi spun out, drawing a yellow flag.

Wheldon, Mutoh and Danica Patrick all decided to forego new tires and fuel and came out in the top three spots. Patrick quickly fell back, finishing sixth, while Wheldon opened up a lead over Mutoh and Andretti that he never let go of.

Pole sitter Scott Dixon, winner of two of the last three races entering Iowa, fell back early and had to rally to finish fourth. Dixon knew he was lucky to earn the pole because rain washed out qualifying, and concerns about his No. 9 car became reality when Castroneves zipped past him for the lead on the opening lap.

But Dixon hung in there, which allowed him to extend his lead over Castroneves in the points race to 48 points.

"Early on, the car was definitely working the way I wanted," Dixon said. "I think strategy played out in the end and that's the way it goes."

Kanaan, who had traded the lead with Castroneves for much of the race, spun out and slammed into the wall with fewer than 40 laps to go. The crash kept Kanaan from a top-five finish for just the second time in seven starts. He finished 18th.

"It's unfortunate because we were having a good race and we were competitive," Kanaan said. "I was setting myself up for the end of the race."

Castroneves led for 71 laps but also finished in the back of the pack. He was forced to change tires because of decreasing pressure on lap 233 and placed 14th — by far his worst finish of the season.

A.J. Foyt IV was fifth.

Mechanical issues claimed Jamie Camara, Darren Manning and Buddy Rice, and Ed Carpenter was knocked out after hitting the wall on the 39th lap. But the second edition of the Iowa 250 went off much better than last year's inaugural race, when colder than expected weather led to slick tires and three accidents.

Officials tweaked the tire specifications to give the drivers more grip on the 0.875-mile oval, and unlike last year, the weather cooperated.

"It was completely different from last year. That made it pretty fun," Andretti said.