The demo version of Supreme Ruler 2020 includes two scenarios in Single Player Mode. The Multiplayer and Campaign Modes are disabled for the demo version. The scenarios included are "Italy Votes" and "Preemptive Strike".
Italy Votes - There is also a walk-through document included with the Demo to explain some of the subtleties of the game particularly relating to a scenario that expects a peaceful resolution.
Preemptive Strike - This scenario showcases the military aspect of Supreme Ruler 2020 with Israel invading Syria.
Both scenarios give the player four game months to acheive their goal. The demo version itself does not have an expiration date, so these two scenarios can be replayed as many times as you wish.