For the seventh consecutive year, there’s an IZOD IndyCar Series championship battle boiling with four races remaining.

Two-time series champion Scott Dixon predicted as much early in the season. The indicators: talented and experienced drivers racing at familiar venues, the new car-engine package leveling the playing field and history (see chart below). And, for the seventh consecutive year, Dixon is in the mix.

Ryan Hunter-Reay of Andretti Autosport (pictured, leading) is a first-time title front-runner, outpacing Team Penske teammates Helio Castroneves (pictured, trailing) and Will Power by less than 30 points. Dixon, of Target Chip Ganassi Racing, is 61 points off the pace.

"It's definitely not out of the question," Dixon said. "The pressure comes on towards the end. We have to try as hard and dig as deep as we can."

Each of the past six seasons, the champion’s margin has not exceeded 18 points over the runner-up, and it appears headed for another down-to-the-finale competition.

The stretch run begins this weekend with the 85-lap Honda Indy 200 at Mid-Ohio, followed by races on another road course, a street circuit and an endurance event on a 2-mile oval.

The top three in the standings have won eight of the 11 races, with Dixon accumulating one victory and a trio of runner-up finishes. The competition throughout the field has been fierce -- 15 different drivers with podium finishes through the 11 races, 19 with at least one top-five finish, and six different teams represented in the top 10 of the standings.

“It blows me away how competitive the series is,” said Hunter-Reay, driver of the No. 28 Team DHL/Sun Drop Citrus Soda car that will display a special paint scheme at Mid-Ohio to include the Pelotonia bike ride Aug. 10-12 in Columbus, Ohio, which raises funds for cancer research. “At Edmonton, the top 22 (in practice) were separated by a second and that is unbelievable to me to think how close it is. To be up there fighting with these guys for the championship is definitely a dream come true.”

Hunter-Reay earned the pole position for the July 22 Edmonton Indy, but started 11th because of a grid penalty for an unapproved engine change following his victory two weeks earlier on the streets of Toronto. He advanced to finish seventh, but believes he left points on the table.

“I don’t think we had the car to win, but the difference between third and seventh in points in that race is massive,” he said.

Castroneves earned his second victory of the season and Power also was on the podium to slice the points deficit.

“(Edmonton) was a great race for us, but with four races left there are still a lot of points to be gained,” said Castroneves, who has three podium finishes in five IZOD IndyCar Series races at Mid-Ohio and will drive the yellow No. 3 Penske Truck Rental car this weekend. “We’re chipping away and hopefully we’ll get what we want.”

Dixon has won three of the past five races on the 2.258-mile, 13-turn Mid-Ohio course, while Power started from the pole and was runner-up in 2010.

“To me, it's the most competitive field I've ever raced in,” said Power, whose field-high gain of 14 positions to third at Edmonton was his first podium finish since winning at Sao Paulo in May. “I've never had to search so hard for speed in my life. Man, it's going to be a fight to the very end.”

Hunter-Reay, whose first IZOD IndyCar Series race was at Mid-Ohio with Rahal Letterman Racing in 2007 (finished seventh), placed third in last August's race. He joined 23 other competitors in testing July 26 -- during which the IZOD IndyCar Series track record lap time was under assault.

"The commitment level is going to be very high as a driver this weekend," said Hunter-Reay, who first competed at Mid-Ohio at age 16 in the Skip Barber series. "We saw much higher cornering speeds at the test and that means it's going to be a very physical race. By commitment, I mean you hold your breath and go into every corner quicker than you think the car can stand and hope you come out the other side. Although qualifying will be at a premium, I think we will be able to pass with the chassis. We've shown at every race so far this year that this chassis allows for more passing.

"We're going to need another race win to win the championship, and that's our total focus."

2012 Championship Standings (4 races remaining)