I doubt they're all pedaling the whole way. I assume there will be wheels on the road 24/7 while some riders sleep.
"In 1986, Pete Penseyres set the all-time RAAM speed record of 15.4 mph over a course of 3107 miles with a time of 8d 9h 47m"
In 2011, only one RAAM rider finished within 9 days, Christoph Strasser, 8 days, 8 hours and 6 minutes. Seven riders finished on the ninth day.