Then, one of the worst things to beset a race leader – a full-course caution on Lap 65 for contact on the tight street circuit – opened the door for Power to challenge Wilson on the restart. That he did in Turn 1 of Lap 72, overtaking the pole sitter of Dreyer & Reinbold Racing to mark the sixth lead change.

“Will got by me and I thought, ‘OK, I’m fine with that.’ I thought we could pass him back,’ Wilson said in sizing up the situation with 13 laps remaining on the 1.75-mile, 11-turn Exhibition Place course. “I was sideways all the way through the last corner. I just couldn’t get my tires warmed up. I ended up sideways through Turn 11, which gave the rundown into Turn 1. Will nearly overshot Turn 1 so I thought I’d have a chance to get back. I had the pace.”

Unfortunately for Wilson, who led the most laps, there was more slipping and sliding on the course marked by patches of concrete mixed with the asphalt. The No. 22 car spun entering Turn 8, ending Wilson’s pursuit to become the eighth different winner in 10 races.

“We had the pace,” Wilson said. “I got sideways through Turn 7, got on the brakes, locked the rears and just couldn’t get them unlocked in time for the corner. I felt like I had a left rear puncture, but the guys came on the radio after and said the car was OK.”

Power still had to get through another restart on Lap 76 (two-lap delay for contact between the cars driven by Alex Tagliani and Tomas Scheckter) in the race of attrition (six cars knocked out by contact, including Helio Castroneves and Scott Dixon). That he did, holding off Dario Franchitti’s green No. 10 Target Chip Ganassi Racing car by 1.2757 seconds to increase his IZOD IndyCar Series championship points lead to 42 over the reigning series champion.

“We worked really hard and this is the end result,” said Power, who started on the front row for the seventh time and won for the fourth this season (two sets of back-to-back races). “I knew just from the marbles and the pick-up that the restart was going to be really slippery. I saw (Wilson) make a mistake coming off the straight so I got a run on him and pulled it off.”

Wilson recovered from the spin, gaining five positions in as many laps, to finish seventh. Seven different teams were represented in the top 10.

“It was a great race for the fans. They saw a lot of action,” said Tony Kanaan, who finished a road/street course season-best fourth in the No. 11 Team 7-Eleven Nestle Pure car. “Fans come out here to see cars make passes and I think we had plenty of those today. For sure, it was one of the hardest races I’ve run this year. We were basically qualifying from lap one until Lap 85. I would have liked to have had a little faster car, but I had a pretty decent race. I tried to battle a lot of people and had to because it was very competitive out there.”

Andretti Autosport teammate Ryan Hunter-Reay, who won at Long Beach, was third in the No. 37 IZOD car for his sixth top 10 of the season. Graham Rahal – making his season debut with Newman/Haas Racing in the No. 02 Quick Trim entry, was fifth. Danica Patrick finished sixth – the same as last year.

“It’s a great confidence-booster not only for me, but the whole No. 7 GoDaddy.com team," Patrick said. "It’s the best finish we’ve had on a street course this season. We were really happy with the way the car was performing throughout the whole race. This is a good way to end a great weekend since we head to another road course next week in Edmonton. Overall, we were strong as a team with the four of us in the top 10.”

Marco Andretti was eighth in the No. 26 Team Venom Energy car. Simona de Silvestro advanced 12 positions to finish a season-high ninth in the No. 78 Team Stargate Worlds/HVM Racing car, and Dan Wheldon was 10th. He recovered from contact on the green flag lap in which the nose assembly of the No. 4 National Guard Panther Racing car was damaged.

Paul Tracy of Toronto, driving the No. 15 Make-A-Wish car for KV Racing Technology, led early based on fuel strategy. But after having to duck in for fuel and tires on Lap 34 and also spinning in Turn 3 late in the race, Tracy fell a lap down. He jumped in to 13th.

“At the end, we could have probably been a top seven or eight, but we struggled the first little bit,” said Tracy, who also will compete in the Honda Indy Edmonton on July 25. “But then the car just seemed to come alive. My pace at the end of the race was the same as the leader, so I was pretty happy about that.

“I just wish we could have qualified better. But we learned some things today and we’ll get better for Edmonton. This was a great week back home with all of the appearances for Make-A-Wish and Honda Canada. I was hoping for a better finish though.”