Kahne began racing open wheel sprint cars at Deming speedway in Deming, Washington, before moving up to Skagit speedway in Alger, WA then he moved to USAC. He was hired by Steve Lewis, who had also employed future NASCAR drivers Jeff Gordon and Kenny Irwin, Jr.. In his first year on the circuit, he was named Rookie of the Year, as well winning the national midget championship, . After that season, he continued to run USAC, as well as the Toyota Atlantic Series and the World of Outlaws.
Kasey Kahne made 20 starts in the Busch Series driving the #98 Channellock Ford Taurus for Robert Yates Racing. His best finish was a tenth-place finish at Cabela's 250. In 2003, he moved to the #38 Great Clips Ford for Akins Motorsports. He won his first pole at Michigan International Speedway and his first Busch race at the Ford 300. He also made a pair of starts in the Craftsman Truck Series in the #2 Team ASE Racing Dodge Ram for Ultra Motorsports, winning in both starts.
NEXTEL Cup career
Kahne replaced Bill Elliott in the #9 Dodge at the end of 2003 when Elliott announced a part-time schedule starting with the 2004 season. Due to the fact that Kahne was still under contract with Ford, a lawsuit began when Kahne decided to go to Evernham, driving a car that was being sponsored by Dodge. Ford eventually got money from Kahne, allowing him to go to Dodge. In 2004, Kahne surprised many by nearly winning several races (including five second-place finishes and 13 top-fives), winning four poles and captured the Raybestos Rookie of the Year award. He drove 30 races for Akins in the Busch Series, finishing fifteenth in points.
He scored his first career NEXTEL Cup victory in his sophomore season of 2005, after a dominating performance in the Chevy American Revolution 400 at Richmond International Raceway. It was also the first victory for the Dodge Charger, which returned to NASCAR in 2005. He also scored two poles in back-to-back weeks at Darlington and Richmond during the same year. He made 22 starts in Busch, splitting time with Akins and Evernham's new #6 team. He won at Texas and Kansas Speedway.
On Monday, March 20, 2006, Kahne won the rain delayed Golden Corral 500 at Atlanta Motor Speedway. Nearly three weeks later, he won the Samsung/Radio Shack 500 at Texas. He has won four races since, among them a season sweep at Lowe's Motor Speedway in the Coca-Cola 600 and the Bank of America 500, holding off Jimmie Johnson, who would go on to finish second in both events. He has also won at California and Michigan.
On September 9 2006, Kahne successfully raced his way into the Chase for the NEXTEL Cup by finishing third at Richmond. Kasey was the 10th and last qualifier for the Chase, edging defending NEXTEL Cup Champion Tony Stewart out by 16 points. Kasey finished 8th in the points, and also won 2 Busch Series races.
During the qualifying sessions for the 2007 Daytona 500, officials found holes in the wheel-wells of his Dodge Charger. A crew member said it was just a tape that covered the hole fell off. Officials said that the tape had been cut. He was one of the four drivers among Matt Kenseth and his two teammates, Scott Riggs and Elliott Sadler whose cars had been found with aerodynamic-improving modifications. His team was one of the six teams caught cheating in the Daytona festivities. Since Daytona, Kasey Kahne has had a hard time keeping up with several back-to-back DNF's.