In most contexts, we’re mostly talking about Single-Winner elections.
In the context of electoral systems, “Congress” and “Senate” are multi-seat legislatures. Hence the talk about proportional representation, IE how many Americans vote Democrat vs how many Democrats get elected. Without that discussion you’ll never get a 3rd party elected.
The senate is voted only within a state, one senator at a time. the house of representatives again is done by states, but has a different number for each state.
In the context of electoral systems, “Congress” and “Senate” are multi-seat legislatures. Hence the talk about proportional representation, IE how many Americans vote Democrat vs how many Democrats get elected. Without that discussion you’ll never get a 3rd party elected.
The senate is voted only within a state, one senator at a time. the house of representatives again is done by states, but has a different number for each state.