McDowell, who only led the NASCAR Cup Series race in the final lap, emerged from a skidding pile-up to grab the lead and win a three-car sprint at the Florida track. It was his first win in the Series in 357 starts.
NASCAR Cup Series driver Michael McDowell (34) celebrates winning the Daytona 500 at Daytona International Speedway.
Defending series champion Chase Elliott finished second while Austin Dillon came in third. Kevin Harvick and Denny Hamlin rounded out the top five.
Xfinity Series drivers Noah Gragson (9), Michael Annett (1), Jeffery Earnhardt (0), Bayley Currey (74) and Josh Berry (8) wreck during the Beef: It's What's for Dinner 300 at Daytona International Speedway.