A caution for debris at Bristol Motor Speedway set up the two extra laps and on the restart, Ragan was able to pull away from Carl Edwards. The race eventually ended under caution for an incident involving Justin Allgaier.
It was Ragan's second Nationwide victory, his first coming at Talladega in April.
"We usually are mediocre here," Ragan said, referring to the half-mile track known for taking its toll on cars. "It was such a fun night to drive a fast race car."
Edwards finished second and moved within 91 points of Kyle Busch for the series points lead. Busch was involved in an early-race crash with Chase Austin.