Born in Bathgate, West Lothian, Scotland, Franchitti began his career in the mid/late 1990s, initially finding his feet in Formula Ford 1600 competing in The Champion of Oulton series against circuit specialists such as Alaric Gordon (Champion 1999, 2001 and 2018). These were times for learning and initially, results were poor and it was not clear that Marino had the talent to succeed. He moved on to Formula Vauxhall in 1998.
In 2001, he began driving sports cars and won the GTO Championship in the British GT Championship series. He joined his brother in America in 2002, and drove in Grand Am and the American Le Mans Series, winning 1 race in the LMP 675 class.
In 2006, he returned to Scuderia Ecosse for their effort in FIA GT as well as making assorted other appearances in high-profile sports car endurance races, including the 24 Hours of Daytona for SAMAX Motorsport.
In 2007, he signed a full-season deal to join his brother at Andretti Green Racing and to be the full-time driver for their new ALMS P2 class Acura entry with teammate Bryan Herta. Dario Franchitti, Tony Kanaan, and Herta teamed up to win the P2 class in the first outing for the team and the car: the 2007 12 Hours of Sebring. Marino started with the team at the next race in St. Petersburg. Both Franchitti brothers left the team after the 2007 season and while Dario went to NASCAR, Marino continued in the ALMS, switching to Dyson Racing's Porsche RS Spyder, partnering with Butch Leitzinger.[2]
For 2012, Franchitti was confirmed as the first driver of the Highcroft Racing DeltaWing, which ran as the 56th and unclassified entrant in the 2012 24 Hours of Le Mans.[4] Marino also drove for the PR1/Mathasian Motorsports PC team in select races, winning in his class at Mid-Ohio.