Cameron was mostly untroubled across the first of two 10-lap heats, save for initially losing out at the start to fellow GRM Peugeot driver Ben Bargwanna.
Still, Cameron was able to fire back in front before Griffins Bend on that opening lap, taking a lead he would hold until the finish.
His final winning margin was the best part of three seconds over Bargwanna.
Dylan O'Keeffe made it a GRM Peugeot podium lock-out with third, while it could have even been a top four sweep had Jordan Cox's car not overheated mid-way through the race.
Will Brown (Melbourne Performance Centre Audi) finished fourth ahead of James Moffat (GRM Renault) and TCR debutant Tim Slade (Wall Racing Honda).
HMO Customer Racing Hyundai pair Josh Buchan and Bailey Sweeny were next followed by Michael Caruso (Ash Seward Motorsport Alfa) in 10th.
That 10th position handed Caruso pole for the second race, the former Supercars full-timer using that to take an early lead.
It was short-lived, though, wit Sweeny passing Tony D'Alberto (Wall Racing Honda) at The Chase on the opening lap before pulling a similar move on Caruso the very next lap.
Caruso lost another spot mid-way through the race, Moffat slipping by at The Chase to slot into second place.
By that point, however, Sweeny was 6.5s down the road and well on the way to a career-first TCR race win, which he ultimately secured by 11s.
Moffat was a lonely second while Caruso defended hard to hold onto third place until the very last lap when Buchan finally got past.
O'Keeffe almost got through Caruso as well, however Caruso could do just enough to hang on to fourth place.
Points leader D'Alberto dropped back to sixth ahead of Bargwanna, Brad Shiels (Royal Purple Racing Hyundai), Cameron and Brown.
Cox looked to be making a good recovery from his Race 1 DNF as he worked his way into eighth place early in the race, only to be run wide at the last corner by Cameron.
That dropped him to 13th although he was able to claw his way back to 11th at the finish.
Slade, meanwhile, had his solid first day in a TCR car undone by a brake issue that saw him retire very early in the race.
Tomorrow's final race will start in the order of accumulated points, with Moffat and O'Keeffe set to share the front row and Cameron and Sweeny the second row.
