According to Aristotle (see Sortition)

It is accepted as democratic when public offices are allocated by lot; and as oligarchic when they are filled by election.

So technically the USA are an oligarchy as is every other state only using elections instead of sortition.

According to Aristotle (see Sortition)

It is accepted as democratic when public offices are allocated by lot; and as oligarchic when they are filled by election.

So technically the USA are an oligarchy as is every other country only using elections instead of sortition.