Virtually all RC election schemes in the US, and also nonpartisan primaries (which are a close cousin) are championed by democrats. That's just not true.
Edit to expand: it's a partisan issue because structurally the democratic party is already a loose collection of interests. They've always structured their internal workings around this kind of dealmaking and coalition-building. Shifting to an environment where those groups (Blue Dogs, DSA, The Squad, the Congressional Black Caucus, etc...) become first class parties doesn't really change the way democrats have always governed.
Under systems like ranked-choice, IRV, etc., having the Green party or Libertarian party on the ballot would be much less likely to harm the near-term prospects for candidates from the two major parties: most of the voters that minor parties would gain are people who currently pick a major-party candidate that has a real chance of winning. Those voters would mostly continue to select a major-party candidate as a second choice.
To get a candidate on a statewide ballot you have to get signatures from a percentage of registered voters. I don't remember the numbers off hand but it's in the tens of thousands. This alone is both cost and time prohibitive. There are also a bunch of other hoops you have to jump through.
Germany is based on the experience of the Nazi's raise to power, one thing Germany got right after WW2 was the German constitution. Stuff like the 5% hurdle to get seats in parliament for example. The US on the other hand still seem to struggle with a system put in place after the civil war to suppress the black vote and satisfy the former confederate states. But I might be wrong.
No need to present your ID to vote, your invitation is enough. Your ID will do if you forgot that invitation.
So in a sense, we have. A mandatory, government run. You cannot be purged, we don't sign ballots (our elections have to be 100% anonymous), we don't need our ID to vote. And any party affiliation is not part of that system. makes stuff a lot easier, and individual parties cannot toy around with it.
This is sort of a dumb idea, really. But it's not as broken as you imagine.
So democrats would oppose a Green or other progressive candidate in (most races in) New York, sure. That's just self-interest. But for the same reason they'd clearly welcome a libertarian entrant. That's not responsive to the discussion.
The claim upthread was that "both" parties oppose ranked choice voting. And that's simply not true.
A single party's goal may be to avoid direct competition but they work together with each other to prevent all other parties. This is one of the things that's easy for them to have bipartisan agreements on.
IMO legislatures should have proportional representation. Sure there are drawbacks but they're not as bad as locking out minority opinions.
Nowadays, that thinking seems wrong. Not sure what yall think over there, but I've always thought of Michael Jackson an American artist, rather than a person from Indiana. I just don't see that Americans see the states as a federation of countries, but I guess people there might.
Something like the UN might have similar votes per country, on the rationale that countries are equal regardless of relative size.
The US when it formed was probably more aligned with what the EU is today. That original setup was very impractical so they reformed into the current US with the Constitution in 1789.
There was an episode during the ratification debates where Rhode Island was almost left out of the United States. 12 other States had already ratified the new US Constitution but Rhode Island held out for more concessions until eventually it was decided that Rhode Island could ratify or leave the Union. Considering they were surrounded by much larger States who had prior grievances with Rhode Island, Rhode Island made the right call. Otherwise they’d likely be part of New York or Massachusetts right now.