The Tigers (8-2, 6-1 Southeastern Conference) remained in Western Division and potentially playoff contention after snapping a three-year losing streak to one of their top rivals. The Bulldogs (9-1, 6-1) came in with the top spot in the playoff rankings and could get a rematch if Auburn can beat No. 1 Alabama in two weeks.
"This was a huge win for us," Auburn coach Gus Malzahn said. "They seized the moment."
Johnson ran 32 times and caught two passes for 66 yards. Stidham threw for 214 yards and three touchdowns, all of 30-plus yards. He also ran for a 7-yard score.
Georgia special teams blunders helped set up three Auburn touchdowns, including a roughing the penalty flag in the first half. The Bulldogs fumbled away a punt return and had a 15-yard personal foul penalty in the third quarter when Auburn pulled away with two touchdowns.
"What made it so lopsided was the uncharacteristic penalties," Georgia coach Kirby Smart said.
Ryan Davis returned a punt 26 yards into Georgia territory, with the flag pushing Auburn even closer to the goal line. Then Davis took a screen pass 32 yards for a touchdown to make it 30-7. Darius Slayton made a 42-yard scoring grab earlier.
The Bulldogs added a touchdown in the final minutes. Chubb gained just 27 yards on 11 carries with a 1-yard touchown on the opening drive. Michel ran nine times for 21 yards.
Jake Fromm was 13-of-28 passing for 184 yards and a late touchdown pass.
"They just whipped us up front," Smart said. "Bottom line, we couldn't move it."
Georgia: Made too many mistakes in the season's biggest game. Fromm faced heavy pressure and was sacked four times. Was trying to move to 10-0 for the first time since 1982 and fourth overall.
Auburn: Had its best all-around performance of the year, making big plays on special teams, offense and defense. Outgained Georgia 488-230 in total yards. Set up a huge Iron Bowl showdown in two weeks, barring a stunning loss in between.
Georgia hosts Kentucky Saturday in its final SEC game.
Auburn plays Louisiana-Monroe in what should probably be little more than an Iron Bowl tuneup.