There's a trigger in the campaign story map called End of Time:
- Timer - Elapsed time is 32767.0 Real Time seconds
- Story - Prepare for Victory to story mode (Difficulty (Difficulty level for player 1))
- Game - End game in Victory for player 1 (Hide dialogs, Hide score screen)
So if you were to idle in storymode for 9.1 hours, you'd beat the campaign.