why don't the primaries get brigaded by opposite party?

One thing I don’t understand about the US political system*. In a lot of states you can register and vote in both primaries (maybe all states I don’t know). What stops Democrats from voting for the least likely to win Republican candidate and vice versa?

*actually sorry theres many things I don’t understand about the US political system.

I don’t think this is true. I believe most states only allow you to vote in one primary election per year.

Some states do allow you to choose what primary election you vote in. So a Democratic voter could choose to vote in the Republican primary (or vice versa) in order to influence the opposing candidate. But by doing so, he’d forego his chance to help choose his own candidate. In some cases, a voter might see that as worthwhile. A Democrat in 2012, for example, would know that Obama was virtually certain to be renominated and could afford to throw his vote away on trying to get a weak Republican opponent.

  1. Only 19 states have any form of open primary.

  2. A lot of people are more interested in voting for the preferred candidate to represent their party in the general election than they are trying to manipulate who will represent the other party in the general. Remember that typically a primary election covers many offices at once, not just the Presidency. So to vote in the other party’s primary excludes you from having any say at all on the shape of your party’s candidates from the highest Federal office to the lowest local municipal office

  3. I don’t think any allow you to vote in both party primaries for the same office, the “jungle primary”/“blanket” format in California allowed you to vote in different party primaries on an office by office basis, but you still couldn’t vote for a Presidential candidate for the Democrats and another for the Republicans. And that system was struck down by the Supreme Court very quickly after California tried to implement it, as violating the political party’s rights of association.

Emphasis added. Which states are these?

None. No states allow you to vote in more than one primary for the same office. As Martin Hyde points out, a minority of states have some form of open primary, meaning you don’t have to be registered with a party to vote in its primary. But you can still only vote in one.

Here is a list of primary types for each state.

Ah ok this is the bit I was missing. How do they enforce this?

The same things that prevent anyone from voting twice in an election.

There are two general methods I’m aware of:

You have to preregister as a member of one party then you get that ballot when you go to the primary.

Both primaries are held on the same day, you show up and ask for one of the two ballots and vote that one. (Or you are given both ballots and you vote one and discard the other so even the poll watchers do not know which party you voted in.)

I do think this sort of thing has happened in local Illinois politics… a lot of questionable election tactics have happened there.

One thing that may not be obvious is that ‘parties’ were not part of the initial design of the US government. In fact, some of the founders expressed worries about ‘factionalism’ and George Washington never formally joined a party. Of course, as a practical matter parties accumulated quickly, but the design at a federal level does not specify parties.

Therefore, there isn’t a lot of federal law specifying how primaries work. Some things were tacked on later for practical reasons, like forbidding states from scheduling primaries ever earlier in order to be first. Each state mostly has evolved a set of rules on its own.

Personally, I think it would be better if we just had ‘top two’ primaries or preference voting or the like and got the government out running elections for political parties, which after all are not formally part of the mechanism of government.

Just as a note in MA it’s ‘modified closed primary’ if you are not registered with a specific party you can choose which ballot you’d like to vote on. If you are registered with a party you may only vote on that parties ballot.

I’m unenrolled and will typically select the Democratic ballot. Voting on the Republican ballot would sacrifice my ability to determine who many of the lower ballot candidates will be. Our lower ballot candidates are majority Democrat, the primary is often the deciding factor on who will get those offices as the Republican candidates don’t have a chance in the general election.

That list is not exactly right for New Hampshire either, since you can change parties at any time, and many people do change at the polling place immediately before voting, and again immediately after. (There’s a separate line to change after voting, so one can see how many people do this.)

In Minnesota, you are given a ballot with Republican candidates on one side and Democratic-Farmer-Labor on the other side. You have to vote on one side – if you vote on both it’s spoiled and they have you vote again.

“to brigade”–gotta look that up. Brit only?

I thought the title said “primates”…same diff. in the end I guess…

Crossover voting is too much work in most states, or not even possible. There were rumors that women were crossing over to vote for Ann Richards for Texas governor in the gubernatorial primary back in the day, but I think that was less “raiding” and more honest support, if it even happened.

Who organizes the primaries? Do the two major parties cooperate, or does the government handle everything?

In the UK, of course, we don’t have primaries. Party leaders are usually well established before the election is called and the leader of the party with the most seats will most likely be PM. Anyone registered to vote can vote for whomever they choose on the day. If there is a local election at the same time, that will be a separate ballot paper, so I could vote for a Conservative MP and a Green Councilor at the same time.

In the US, would it be normal for everyone to know who their state representative is? Here in the UK, I doubt if 3 out of 10 random people could name their MP. As for their EU representative (MEP) the ratio would probably be in the high 90s from 100.

AFAIK - not American - there’s one primary election for each full election. It’s not like you can vote in the Republican primary, then go down the street to the Democrat polling booth and vote there - they are the same polling station. So pick one.

As others point out, many states make you register as one or the other, so buying two party memberships does not gain you anything. (Don’t need to be a paid-up member in the USA, just declare your leanings as I understand).

The other point is, as I understand, you are voting the full gamut. The USA is legendary in Canada as the place where even dog-catchers are elected. By selecting a political party choice, you are allowed to primary vote for all positions at once for that one party (maybe even in a butterfly ballot?)

So selecting one party to vote for the worst presidential candidate, means you are not able to vote for a good candidate from your favourite party for congress or senate, where all the work is (not) done. Or mayor, governor, state legislature, bridge lane-closing committee, school board, etc. Or dog-catcher.

The way it works here in SC, they’re held on consecutive weekends but they use the same sign in sheet. So if you’ve already signed in to vote in the first primary you can’t vote in the second.

I have crossed over to vote against a candidate who I found very scary and did NOT want to be the Republican nominee. I personally don’t think there’s anything wrong with that; I was voting out of sincere feeling, to hopefully get a general election candidate that was more acceptable to me.

Right but it seems to me that in say a solid Red state where Democrats aren’t going to get elected anyway, the local Democrat party bosses could instead call on their voters to register republican and vote for the least popular republican Presidential candidate. Is there anything illegal if they were actively encouraging voters to do that?

Oh and “to brigade” is internet forum slang, to mean invade another message board en masse.