Helio Castroneves didn't need any reminders.

He leads the IRL points race by the slimmest margin, so when he lines up for the PEAK Antifreeze Indy 300 at Chicagoland Speedway, his stomach will be rumbling.

He has two Indianapolis 500 championships and 11 victories in 79 starts, to go with just under US$9.4 million in career earnings. One thing he doesn't have, though, is a IRL series championship, and that could change Sunday.

Castroneves (441) has a one-point lead over Marlboro Team Penske teammate Sam Hornish Jr. heading into the season finale, with Target Chip Ganassi Racing's Dan Wheldon and Scott Dixon 19 and 21 points behind.

``It would definitely be a dream come true,'' Castroneves said.

He would love to give owner Roger Penske his first IRL Cup. So would Hornish.

Either way, they want to keep the championship from Ganassi.

``We want to get this championship for Roger,'' Castroneves said. ``Whether it be me or whether it be him, we don't want a Ganassi taking advantage of that.''

Of the four contenders, Castroneves is the only one without a points title, so he playfully suggested Hornish step aside if the race comes down to those two.

But he realizes a championship won't come without a fight _ from a contender or any other racer.

``Some people have to maintain the respect for others on the track,'' Wheldon said. ``I think at the end of the day, somebody who's desperate for a win could quite easily wipe out one of us. It wouldn't be right, but it happens a lot at a track like this where it's very difficult to break away.''

The Penske and Ganassi teams have a combined 11 victories this season, with Castroneves and Indianapolis 500 winner Hornish each finishing first four times. Defending points champion Wheldon won the season opener at Homestead-Miami Speedway, while Dixon drove to victory lane at Watkins Glen in June and Nashville in July.

No other team reached the winner's circle until Andretti Green's Tony Kanaan won the Milwaukee Mile, the year's 10th race. Marco Andretti won last week at Infeon Raceway.

Otherwise, teams not named Penske or Ganassi are playing catch-up.

Wheldon got off to a good start after jumping from Andretti Green but frustration came at the Indy 500, when he led for 148 laps only to have a punctured tire deflate his hopes for a victory. He finished fourth.

``For some reason, we're still very close to the lead and the championship,'' Wheldon said. ``As many mistakes as we've made, I don't think we deserve to be. You can't make mistakes when you're up against Penske.''

Sunday figures to be a difficult day, though.

It's the third time in five years the championship has come down to the final event. And once again, Castroneves and Hornish are vying for the title _ this time with Wheldon and Dixon in the mix.

In 2002, Castroneves and then-teammate Gil de Ferran were a point apart with two races remaining, but a crash at Chicagoland knocked de Ferran out of contention. Hornish, with Panther Racing at the time, took first that weekend and then beat Castroneves in the third-closest finish in IRL history at Texas Motor Speedway for his second straight series championship.

Now, Castroneves has another chance.

``There's always something that went wrong,'' he said. ``If it wasn't your mistake, it was something about the car that happened. The equipment that you chose was wrong. You have so many variables.''