INDIANAPOLIS — Helio Castroneves understands better than most how hard it is to win the Indianapolis 500.

The charismatic Brazilian won as a rookie in 2001 and then backed it up with a victory the next year, becoming only the fifth driver in the history of Indianapolis Motor Speedway to win two in a row.

Since then, six years have passed with no fence-climbing celebrations at Indy for "Spiderman."

"The first year was pretty tough," Castroneves said. "The second year was even tougher. The third year, I had like a bullet. This car was incredible, supersonic. I finished second. So, I learned that you can't let opportunities go by. You've got to go for it. That's what we're going to do this Sunday."

A win this year would be particularly significant for Castroneves. On Friday, federal prosecutors dropped the remaining tax evasion conspiracy charge against him and his sister, clearing Castroneves of all the charges that once threatened to derail his career.

In just his third race since returning to the series, Castroneves will start from the pole Sunday, with Penske Racing teammate Ryan Briscoe next to him in the middle of the front row. That 1-2 punch gives team owner Roger Penske a good shot at his 15th Indy win.

"We've got a good chance this year with two cars on the front row," said Penske, who last visited Victory Lane with Sam Hornish Jr. in 2006. "But, to win here, everything has to work perfectly, everything."

Penske had a 1-2 finish in 2003, with Gil de Ferran outdueling Castroneves. This time, Castroneves would love to give the team another sweep — only with himself out front. Rising star Briscoe could make that difficult.

Although Castroneves is the oddsmakers' favorite, Briscoe is the one who could give Penske a new face on the Borg Warner Trophy.

"Winning this race comes from the preparations and the leadup to it, what you've done in the three weeks here," the Australian driver said. "I honestly feel as though we couldn't have done a better job this month. We've really got a good feeling with the car setup and what we need to do going into the race."

Good enough to go 1-2-3?

Penske has a third entry for the first time since 1994, when Al Unser Jr. gave him a win. Will Power, hired to fill in for Castroneves until his legal problems were resolved, was rewarded with a drive at Indy after Castroneves returned to the cockpit.

The Aussie, starting from the outside of the third row, might be the most motivated of the Penske drivers as the team has not guaranteed him any more races.

"I know I have a great car and a great team," Power said. "I'm going to do the best job I can and we'll see what happens. I don't believe this will be my last race for Penske."

Briscoe figures with all that firepower the team has a very good chance for success.

"Hopefully, just doing everything right and minimizing the mistakes is what it will take to win the race," Briscoe said.

Nothing is ever a sure thing at Indy, though.

Tony Kanaan is a good example. He has raced at Indy seven times, led the race each year — a record — and has yet to finish better than second (2004).

"Maybe this will be our year because nobody has been saying much about us," said Kanaan, starting from the outside of the second row. "I know I could have won this race a couple of times by now, but you need a good car, good strategy and a little good luck. Maybe it will all happen this time."

The people's favorite is IndyCar glamour girl Danica Patrick. Unlike past years, she hasn't been very visible this month, never among the fastest drivers in practice and 10th on the grid after a disappointing qualifying effort.

Like Andretti Green Racing teammates Kanaan and Marco Andretti, Patrick has a car that has been more consistent than fast. And that's just fine with her.

"I really think I've got a great shot," she said. "I've got more experience, which I really think does pay off here."

Longtime open-wheel star Paul Tracy won't have that in his favor Sunday.

Back at Indy for the first time since losing to Castroneves in 2002 in a controversial finish, Tracy will start from the inside of the fifth row. He insists he won that race, passing Castroneves moments before a caution flag waved, freezing the field. After considerable investigation and six weeks of deliberation, race officials disagreed.

"I've got no grudge, but I still believe I won that race," said Tracy, the leading active driver with 31 career victories.

This time, he wants to leave no doubt.

"I'm not here just to race and have a good day," Tracy said. "I want to win."

But it's Castroneves who's already working a winning streak, taking his third Indy pole and the annual pit stop contest.

"I feel very lucky," Castroneves said. "My life is starting all over again. I'm having fun doing what I love doing best, and I'm going to try to win Indy again. It is definitely going to be an interesting race."