Sorensen, who finished second in 2013 as well, got ahead of front row starter Jazeman Jaafar at the start, and was Nato's only challenger from then on.
The Dane got the gap down to under a second early in the race, but for the majority of the 30 laps Nato was able to keep him a safe distance behind.
Jaafar also repeated his result from last year by taking third, fending off championship leader Carlos Sainz for the duration of the race.
Sainz mounted several attacks in between backing off to give himself a run at the Malaysian, but he could never quite carve out a serious chance to take a podium spot.
The Spaniard also had to keep an eye on his mirrors as title rival Oliver Rowland was able to join the fight for third in the second half of the race.
Rowland had briefly got ahead of Sainz at the start, but after the Briton ran wide at Saite Devote the pair battled side-by-side until the exit of Casino Square, with Red Bull junior Sainz coming out on top.
Behind them, Zoel Amberg held off the other Red Bull-backed car of Pierre Gasly for sixth, while Caterham junior Will Stevens had a lonely race to eighth at what he declared Strakka's worst circuit.
Sauber F1 test driver Sergey Sirotkin's hopes of a good result from sixth on the grid were dashed as soon as the race began, as his car stalled when the lights went out.
The Russian later retired after a spin at the final corner.
Results - 30 laps: Pos Driver Team/Car Time/Gap 1. Norman Nato DAMS 42m34.878s 2. Marco Sorensen Tech 1 +0.790s 3. Jazeman Jaafar ISR +12.228s 4. Carlos Sainz Jr DAMS +13.268s 5. Oliver Rowland Fortec +13.960s 6. Zoel Amberg AV Formula +20.962s 7. Pierre Gasly Arden +21.395s 8. Will Stevens Strakka +31.911s 9. Robert Merhi Zeta Corse +38.853s 10. Meindert van Buuren Pons Racing +50.019s 11. Marlon Stockinger Lotus +55.954s 12. Oliver Webb Pons Racing +1m00.594s 13. Matias Laine Strakka +1m00.803s 14. Luca Ghiotto Draco +1m00.874s 15. Pietro Fantin Draco +1m03.676s 16. Will Buller Arden +1m04.448s 17. Beitske Visser AV Formula +1m14.137s 18. Andrea Roda Comtec Racing +1 lap 19. Roman Mavlanov Zeta Corse +1 lap Retirements: Sergey Sirotkin Fortec 6 laps Matthieu Vaxiviere Lotus 1 lap
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