He finished 0.2 seconds ahead of Gilliland in the two-lap overtime finish, garnering just his second career Sprint Cup Series victory in a race that was marked by two major crashes and 3 1/2 hours of rain delays.
Ragan's only other win came in 2011 at Daytona International Speedway when he drove for Roush Fenway Racing.
The first pile-up came on Lap 42 and involved 16 cars, with the second coming four laps from the scheduled finish. The latter crash took out Jeff Gordon, Kurt Busch, Danica Patrick and Clint Bowyer, among others.
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