For any number of players.
Anyone starts the game in a group by placing their hand to their ear as if they’re listening to an earpiece. Anyone else in the group who sees also places their hand to their ear in the same way. Once there is everyone but one person who is listening to an earpiece, either because they’re oblivious to the game or because they’re slowest to react, that one person becomes the President. Everyone immediately runs to and dogpiles on the President yelling “get down Mr. President!”
It’s useful to teach everyone the game up front, then play when there’s one new friend who doesn’t know it. It can also be played if there’s a critical mass of secret service agents who through eye contact decide who the President will be.
This takes some practice to get going with.