Lewis hit a solo home run in the fifth and Lyle Allen gave Georgia a 4-0 lead with a three-run homer with two outs in the eighth.
Michael Palazzone (2-0) allowed just one hit in three innings to pick up the win. Will Harvil and Dean Weaver pitched the final two innings to seal the Bulldogs' fourth straight victory.
Alex McRee pitched four innings in his first weekend start since Feb. 28. He struck out five batters in the first three innings and got out of bases loaded jams in the second and third. Mississippi State (13-8, 2-3 SEC) stranded eight runners through the fourth inning and left 12 on base for the game.
"Alex wasn't quite as sharp today, but he did a good job of getting out of some situations," said Georgia head coach David Perno. "Palazzone did a great job out of the pen as did Will and Dean."
Both teams finished with five hits apiece, and Lewis had two for Georgia. He led off the ninth with a double, and after Levi Hyams drew a two-out walk, Lyle Allen blasted his second home run of the season to give the Bulldogs a four-run lead.
Colby May had a double and Rich Poythress extended his hitting streak to 10 games with a single in the second inning.
Nick Routt (2-1) tossed eight innings and took the loss for Mississippi State.
The record crowd came a day after the Bulldogs had 3,876 on Friday, the third largest regular season at Foley Field.
"It is a huge advantage for us to keep getting crowds like this," Perno said. "I'm so happy to see this many people out at the park and hopefully we'll keep getting better so we can keep drawing this many fans. They've been really great the last two days."
Justin Grimm (1-1, 5.49 ERA) will get the start for Georgia in the series finale Sunday at 2 p.m.