The American's 180-yard second shot at the par-four 15th found the bottom of the cup as he carded a three-under 68 for a 12-under total of 130 at TPC Deere Run in Silvis, Illinois.
Amazingly, he holed out from the fairway in Thursday's opening round as well.
"I guess holing out two days in a row is always nice," said Ghim, who also had a chip-in for birdie. "It just felt like a huge, huge boost so it helped me stay more patient because something good happened to me there.
"It's been a couple years since I think I holed out from the fairway. To get two on back-to-back days is great."
Ghim, 29, is aiming to become the 25th player to earn a maiden PGA Tour victory at the John Deere Classic, but he'll have no shortage of challengers heading into the weekend. Five players sit just one shot back at 11-under 131.
Among them is defending champion Davis Thompson, who fired a sizzling eight-under 63 with eight birdies, and Max Homa, who started the day one behind and stayed there after a steady three-under 68. Argentina's Emiliano Grillo joins Americans Brian Campbell and David Lipsky in the group at 11 under.
Six more players are just two shots off the pace at 132, with the third round moved to an earlier tee time due to forecasted evening thunderstorms.
"The leaderboard is so bunched," Ghim added. "(I will) just kind of keep my head down and try to birdie some par-fives and roll in a couple more 15-footers."
Lucas Glover and Zac Blair share the first-round lead at the John Deere Classic after both carded seven-under-par 63s, while hometown favourite Zach Johnson sits just one shot back following an impressive finish.
Viktor Hovland has a one-stroke lead over Scottie Scheffler heading into the final round of the Travelers Championship on Sunday.
Scottie Scheffler came within inches of making PGA Tour history on Friday, carding a brilliant 10-under-par 60 to take the clubhouse lead at the Travelers Championship.
Eric Cole has a one-shot lead at the top of the Travelers Championship leaderboard after the opening round, but Scottie Scheffler lurks in the chasing group.
