Gangjee, who shot a 79 on the first day, added a three-over 73 to total 152 and finish the week early. He birdied just once on the ninth but double-bogeyed the fourth and bogeyed the 10th and 12th.
Swede David Lingmerth recovered from a triple-bogey to shoot a four-under 66 and take the 36-hole lead. Lingmerth rallied with three birdies on his final six holes to close at eight-under 132 at TPC Potomac at Avenel Farm.
Josh Persons (68) and Canada's Brad Fritsch (66) are one shot back heading into the weekend.
Yesterday's second round was halted by darkness with three players left on the course. As a result, the trio will return to finish Saturday morning.
A total of 67 players are projected to make the cut, which will be at two-over 142.