Before transitioning to stock cars, Santos established himself as a leading midget racer, competing in the Northeastern Midget Association, USAC, PRA Big Car, and ISMA series. His breakthrough came in 2006 when he led all USAC National Midget Tour drivers in wins, collecting five victories including a notable win at O'Reilly Raceway Park on the Night Before the 500. This performance earned him a signing with Bill Davis Racing.
Santos made his stock car debut in 2006 at Iowa Speedway for Bill Davis Racing, starting tenth and finishing sixth in the number 02 Dodge. Returning in 2007 in a Toyota Camry, he won Toyota's first stock car pole position at USA International Speedway in Lakeland, Florida, demonstrating early pace in the new machinery. He posted additional top-five finishes at Kentucky Speedway that season, though mechanical failures and racing incidents interrupted several strong efforts at Kansas and Pocono.
Santos debuted in the NASCAR Busch Series in 2007 at Richmond International Raceway for Riley D'Hondt Motorsports, qualifying seventh in the number 91 Toyota before finishing thirtieth after spending the early laps in the top ten. He also qualified fourth for the Camping World 200 at New Hampshire Motor Speedway and ran in the top ten before contact from a lapped car ended his charge. He completed two additional races for the team without improving on those results.
Santos found more success in the NASCAR Whelen Modified Tour, collecting his first two wins at Thompson International Speedway in October 2007. He won the season-opening Icebreaker at Thompson in April 2010 and converted that momentum into the 2010 Whelen Modified Tour championship, finishing the season with four wins and four poles.
In 2011, Santos ran the Nationwide Series opener for Jimmy Means in a backup JR Motorsports car after the primary number 52 was damaged in practice. He drove the race in its entirety and finished seventeenth. He returned to the Nationwide Series in 2012 for part-time duty with Tommy Baldwin Racing while continuing to compete in the Whelen Modified Tour for the Tinio Corporation number 44.
Santos returned to his open-wheel origins after his NASCAR stint, racing the full NASCAR Whelen Modified Tour for Bob Garbarino's Mystic Missile Racing team and competing on limited schedules across all three USAC divisions. He made select appearances in the NEMA ranks in 2009.
His post-NASCAR career produced some of his most significant results. Santos won several of American short-track racing's most prestigious events, including the Turkey Night Grand Prix and the Copper World Classic. In 2020, he won the Little 500 USAC Sprint car race at Anderson Speedway, one of the most storied short-track events in American racing. He also registered back-to-back wins in the Musket 250 in 2019 and 2020, cementing his reputation as one of the top sprint and midget car drivers in the country.
Santos represents a generation of versatile American short-track racers who moved fluidly between open-wheel and oval disciplines at the national level. His 2010 Whelen Modified Tour championship stands as his most prominent series title, while his wins in classic American open-wheel events like the Turkey Night Grand Prix, Copper World Classic, and Little 500 reflect the breadth of his accomplishments across multiple racing formats. His family ties to New England motorsport and his continued presence on the national short-track scene have made him a recognizable figure in American grassroots racing.