The race was postponed from Friday evening due to heavy rain around the three-mile course in County Antrim, with Todd lining up on pole on the Milenco by Padgett’s Honda.
Held on a damp but drying course, Todd shot into the lead and held a slender lead of 0.4s over Ballymoney man Darryl Tweed, who had moved into second place corrected time after starting from the second group. Adam McLean was holding third from Paul Jordan and Mike Browne.
There was nothing to separate the top six after three laps, but Tweed was now ahead of Todd by only 0.26s, with McLean still third on his Yamaha R6 from Jordan, Browne and Derek Sheils on the McAdoo Kawasaki.
Todd led on the roads but it was Tweed who stayed in front on corrected time by just over a tenth of a second until the sixth and final lap, when Todd upped the ante to clinch victory by 0.315s from Tweed, who rode a fine race on the Wilson Craig Honda.
McLean sealed the final podium place with Dominic Herbertson climbing to fourth on his Kawasaki ahead of Jordan, while Browne completed the top six on the Burrows Yamaha. Sheils and Michael Sweeney (Yamaha) were the top eight.
The race was restarted over six laps after an incident on the opening lap at Church Bends, when Andy McAllister and Stephen Tobin crashed out unhurt.
Earlier, Keelim Ryan was a runaway winner of the Lightweight Supersport race – postponed from Friday – on the Faraldo Racing Yamaha 450 by 18.9s from Tweed (M&D Kawasaki), with Kris Duncan almost seven seconds further back in third.