The race, which was stopped three times for wet conditions, will resume Monday at 1 p.m. and will be broadcast live on FOX Sports.
Larson's No. 42 Chevrolet pulled away during the race's last green flag run as the rest of the field raced each other hard behind him. His big lead ended when the track became too wet to race on and the race was put under caution. It was stopped at lap 204, just 46 laps from becoming an official race, before a 5 p.m. decision to postpone.
Larson didn't predict how the track conditions would be once the race resumes.
"You never know how the track is going to change, especially with the VHT (sprayed in the turns to add grip)," he said. "It seems like it's different every time we come here. We will just try to learn throughout the race and adapt to it. But I feel the balance of my race car is pretty good. I was taking it pretty easy, even though I know they were racing hard behind me. I have good drive off (the corners) and think I would have checked out."
He had checked out already with Denny Hamlin in the No. 11 Toyota battling from fourth to second during the last segment. Paul Menard was running third in the No. 21 Ford, followed by pole sitter Kyle Busch in the No. 18 Toyota and Ricky Stenhouse Jr. in the No. 17 Ford.
BUSCH FADES EARLY
Pole sitter Kyle Busch got out to an early lead, but was passed by Ryan Blaney after the first caution and faded back to ninth when the race was halted for rain after 49 laps. Busch's car improved over the course of the 204 laps and he had worked his way back into the top five, turning the fastest lap times at the end.
"My car was really bad on the short run," Busch said. "After about 40-45 laps, I got start picking guys off and working my way to the front. Hopefully, we can get back to that and get some longer runs where I can get up there and battle with Larson."
Knoxville driver Trevor Bayne was in a position to get back on the lead lap on lap 118 when his No. 6 Ford was hit from behind by the No. 37 of Chris Buescher. It got Bayne's car sideways, where he hit Harrison Rhodes and triggered a multi-car wreck that collected race leader Blaney, who had led 99 laps in the No. 12 Ford to that point.
Bayne spun out again on lap 154 and was running one lap down in 25th when the race was halted.
Chad Finchum, making his NASCAR debut, was running 31st after spinning out on lap 140 in his No. 66 Toyota.