"Helio has had a pretty stress-free year as far as not being involved in accidents or having mechanicals," Dixon said. "I think it's still going to be a tough battle. I like the look of the tracks we have coming up. I think we are in the hunt."
Castroneves, who finished second to Dixon on Sunday, isn't giving up and doesn't view Dixon as any bigger of a threat than he did defending series champion Ryan Hunter-Reay, who was second in the standings until this weekend.
"Both are champions ... they've been there," Castroneves said. "We just got to keep focused on our work. I'm not worried less or more because it's Scott. The same thing was with Ryan. They're both great teams. But I trust my guys. I know we have the best equipment, the best guys out there. We know what we are capable of, that's what we're focused on at this point."
But the three-time Indianapolis 500 winner admitted Sunday he desperately wants his first series championship.
"I want it as bad as anybody especially having those guys behind me," he said. "I have that chance. I'm going to fight as much as I can. If I have a good car to finish, I will finish strong. If I don't have a good car to finish, I'll play smart. I want it more than anybody."
Dixon was barely challenged at Exhibition Place, needing to pull off two late restarts to preserve what was otherwise an easy Sunday drive.
The win was the 32nd of his career, and moved Dixon into sole possession of seventh on the all-time wins list. His victory Saturday moved him into a tie with teammate Dario Franchitti, Sebastien Bourdais and Paul Tracy, but the 32-year-old New Zealander is on the hunt for much more.
His sweep of the Toronto doubleheader also earned Dixon a $100,000 bonus from IndyCar sponsor Sonax.
"100 grand is good, but I'd rather have the points. Points are why we're here," said Dixon, who moved ahead of Franchitti by one victory.
Castroneves never had anything for Dixon.
"They were in a different league, Scott and Ganassi guys, I was pushing," Castroneves said. "Whatever he is taking for breakfast, I want it. Scott, tell me what you're having for breakfast. Let's be realistic the guy was leading the whole race, 13 seconds ahead."
Bourdais was third for his second podium finish of the weekend after not finishing in the top-three in American open-wheel since 2007. On Saturday, his second-place trophy slipped off its pedestal and shattered as he was presented with it on the podium. Sunday was a successful handoff as Bourdais picked up the trophy without a pedestal.
Toronto native James Hinchcliffe had a rough weekend an issue with his throttle prevented him from starting the race with the rest of the field. He finished 21st, four laps behind the leaders.
Carlos Munoz, who got a call from Panther Racing late Saturday night to replace Ryan Briscoe who broke his right wrist, finished 17th. It was the second IndyCar race of the 21-year-old Colombian's career, first on a road course.
Franchitti, who had third place stripped of him Saturday and then restored after a penalty, was fourth as Target Chip Ganassi Racing has seemed to turn itself around over the last week. Winless until Pocono, Dixon and Franchitti are formidable threats again.
E.J. Viso was fifth and the highest finishing Andretti Autosport driver after defending series champion Ryan Hunter-Reay was involved in an accident on the final restart with Will Power that took both Hunter-Reay and Power out of contention for third place.
"I talked to (Power) and he just said he got loose on the bottom and he just drove right up into us," Hunter-Reay said. "I don't think he drove into me on purpose, but we were taken out of the race. We had a good day going and had a decent car."
Charlie Kimball was sixth as Ganassi's three drivers claimed three of the top six spots.
-AP
