In his time away from Congress, Marlin was a successful entrepreneur in the manufacturing, agricultural, and food service spaces. He and his wife, Christy, also previously owned a farm-to-fork dinner theater that was accompanied by a meat processing facility where they raised Wagyu beef which was served to attendees during performances.

Marlin's business journey began at 16 when he launched his own beef cattle operation. By 18, he had joined his father, Albert, and other family members in growing the family business into a multi-million-dollar enterprise.

At just 25 years old, he was elected to the Indiana State House as its youngest serving legislator, balancing his political duties with full-time work in the family business. During his tenure, he played a key role in helping Governor Mitch Daniels eliminate a $1 billion deficit, turning it into a $1 billion surplus while fully funding a 10-year roads program-all without raising taxes.

After a term in the Indiana State Senate, Marlin was elected to the U.S. House of Representatives in 2010. In his previous time in Congress, he authored the Conservative Congressional Budget and was the original sponsor of the Right to Try legislation, which was later signed into law by President Trump.