Whitt was drawn to racing after seeing his cousin Brandon with a go-kart. After winning championships in karting, he moved to sprint cars in 2004 and was quickly noticed by Red Bull, reaching the semifinals of their driver development search. He won the Hoosier Sprint Rookie of the Year award in 2006 and in 2007 traveled the country running sixty races with thirty-four top-ten finishes. Relocating with his mother to Lebanon, Indiana, to pursue USAC racing full-time, Whitt became the youngest winner of the USAC National Midget Championship in 2008, also winning the Hut Hundred that year. In 2009, driving for Keith Kunz, he raced in Silver Crown, Sprint, and Midget events and collected seventeen wins.
Whitt moved to stock cars in 2010, the same year he won the USAC Super License award. He ran for the Camping World East Series championship, winning the pole in his first start at Greenville-Pickens Speedway and finishing fourth in the series standings. He made his Nationwide Series debut at Phoenix International Raceway late that year, finishing fifteenth.
In 2011, Whitt drove in the Truck Series for Turn One Racing. After failing to qualify in the No. 60 at Daytona, he drove the No. 93 for RSS Racing before returning to Turn One. He won the pole at Darlington and became the first rookie to lead the Truck Series points after Charlotte, finishing ninth in the year-end standings. He also drove a third Team Red Bull entry in the Sprint Cup Series in the final two races of the 2011 season at Phoenix and Homestead.
With Red Bull exiting racing after 2011, Whitt signed with JR Motorsports to drive the No. 88 Chevrolet in the Nationwide Series in 2012, competing for Rookie of the Year. In 2013, after parting with JR Motorsports due to sponsorship issues, he joined Tri-Star Motorsports from Dover onward and earned his first top-ten of the year — an eighth at Road America. Late in 2013, he substituted in seven Cup races for Swan Racing Company replacing David Stremme.
Swan Racing hired Whitt for the full 2014 Cup season in the No. 26. A highlight of his 2014 Daytona 500 campaign came in the Budweiser Duel qualifying race, where he gained eight spots in the final five laps to earn his transfer spot. In the 500 itself, he ran as high as fourth before mechanical issues and a late crash dropped him to 28th. Swan Racing's financial difficulties led to Whitt's car being absorbed by BK Racing mid-season, where he continued to accumulate 2014 points. His career-best Cup finish at that point came at the GEICO 500 at Talladega: fifteenth place.
Whitt joined Front Row Motorsports for 2015 in the No. 35 Ford, with Speed Stick GEAR and Rinnai as sponsors, again finishing 31st in points but improving his career-best Talladega run to thirteenth. After FRM shut the No. 35 down, Whitt moved to Premium Motorsports in 2016, where superspeedway speed again surfaced: he finished eleventh at Daytona in the summer race and eighteenth at Talladega, both career bests at the time. However, he missed the 2016 Daytona 500 after spinning and breaking his transmission during his Duel qualifying race.
For 2017, TriStar Motorsports signed Whitt for a full chartered Cup season in the No. 72 Ford. At the Daytona 500 he qualified seventeenth, led three laps in the final stage, and finished eighteenth. His strongest run of that season came at Indianapolis, where the team avoided crashes to finish twelfth. He stepped back to a part-time role with TriStar in 2018, with his final NASCAR start coming at ISM Raceway in November of that year.
A notable moment in Whitt's career came late in the 2016 Ford EcoBoost 300 at Homestead, the Xfinity Series season finale. Running in TriStar's No. 14, Whitt was on the lead lap at a late restart without fresh tires, restarting first. His slow start allowed Daniel Suarez and Elliott Sadler to clear him, while Erik Jones and Justin Allgaier were held up behind him — critically affecting the title battle. Suarez won the championship; Jones harshly criticized the restart while Allgaier was more measured. Whitt later apologized, partially attributing the slow start to Jones making contact with him.
In 2024, Whitt returned to his roots in motorsport by competing in desert racing with a Volkswagen Beetle built by Sletten Engineering and Isenhouer Brothers Racing. He and the Beetle finished fifth in Class 11 at the 2025 Battle at Primm. In 2025, he won the Class 11 World Championship at Crandon International Off-Road Raceway.
Whitt's career arc — from youngest USAC Midget champion to a full-season Cup charter holder and back to off-road racing — reflects both the opportunities and the structural limitations facing independent NASCAR competitors. His superspeedway results consistently punched above his equipment level, and his dirt and open-wheel background gave him raw versatility that periodically surfaced even in NASCAR's most resource-intensive environment.