Primary elections are how political parties in the United States pick their strongest

candidate to run for president.

The parties do this by holding many elections in each of the states and the candidates with

the most votes from these elections becomes the party's official nominees.

These nominees then face each other in the national election for president.

But this isn't the whole story.

There are five things that make it a bit more complicated than that.

Complication number one, primaries versus caucuses.

In every state, the local party leaders decide how to run their elections.

The two most common choices are primaries and caucuses.

Primaries are just like standard elections.

Go to the polls whenever you can, stand in a long line, hide in a booth, then tick a box or press a button, and your vote is cast in complete anonymity.

A caucus, however, is a public vote. People gather in groups wherever space is available, then literally take sides in a room with everyone else who likes the same candidate.

The groups debate each other, and, if people change their minds, they need to physically switch sides.

At the end of the debates, the party representatives count the number of people in each group. If you leave too early, your vote doesn't count. This description of primaries and caucuses is really all you need to know, but the specifics can vary wildly. That's because there are 50 states, all of which hold at least two primaries and caucuses for the big parties and possibly more for the small parties.

Covering all the local variants would take a tediously long time, which your short attention span for boring political videos wouldn't tolerate. And you need to stay focused because there are four more things to come. Complication number two, who can vote? In the national presidential election, all American citizens over the age of 18 can vote, with two exceptions. You can't live here or here. But primaries are in state elections with lots of different rules. Most states and parties

will only let you vote in the primary if you're an official member of the party. This is called

a closed primary because the voting is closed to non-party members. But some citizens are

independents and not registered with any party. If you're an independent and live in a state with closed party elections, tough luck. No voting for you. Some states, however, have semi-closed primaries where independents can pick one and only one primary to vote in. Parties allow this because the presidential election is often determined by independents, so knowing which candidates they like is useful. Finally, a few states and parties really play it fast and loose with open primaries. Here, any citizen, no matter which party they're registered with, can pick a primary to vote in. But it's not just the states that have primaries. They're also held in the District of Columbia and the off-forgotten territories. Holding primaries here is a bit odd, though, considering that territorial residents can't vote in the actual presidential election.

Lastly, are the Americans living abroad who, depending on the party, vote in a block as though they all live together in one big extra state.

When all these elections take place depends on... complication number three. Who votes when?

Primaries aren't conducted all at once but are spread out over a year.

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