Jenkins went 15 of 21 for 122 yards and a touchdown pass and rushed for 82 yards.
Jacksonville State (1-1) outgained Chattanooga 409-111. The Gamecocks went 67 yards on six plays on the opening drive, capped by a Miles Jones 12-yard touchdown run. Chattanooga (0-2) tied it on Dee Virgin's 55-yard interception return.
A 4-yard touchdown run by DaMarcus James and a 42-yard field goal by Connor Rouleau gave Jacksonville State a 10-point lead, but Lucas Webb intercepted a Max Shortell pass and returned it 37 yards to make it 17-14 at the break.
Rouleau's second field goal of the day made it 20-14 in the third. But the Mocs got a pair of Henrique Ribeiro field goals to tie it with 12:19 left.