Republicans like to talk about freedom. Democrats like to talk about democracy. Neither of them walk the walk.
For the first time since the 1940's New Yorkers will only have two choices for governor.

The paucity of options is largely due to former Gov. Andrew M. Cuomo, who championed changes in election law two years ago that made it far more difficult for third parties to get on the ballot. The changes to ballot access law tripled the number of voter signatures required for groups to get on the November ballot and forced political parties to qualify every two years instead of four.

The steep climb to get on the ballot has prompted legal challenges, including one being heard this week in State Supreme Court in Albany, in a lawsuit filed by the Libertarian Party. The party’s nominee for governor, Larry Sharpe, argued that the rules are so tough that only the entrenched and connected can earn the right to appear on a ballot in New York.

Both parties have worked hard at keeping third parties off the ballot, and it's not just true for Blue States.
The Texas Republican Party sued to get 40 Libertarians kicked off the ballot in 2020 and sued again to get another 23 Libertarian candidates off the ballot in 2022.

However, it's the Democrats that have been the most hostile to democracy.
The Green Party already doesn't exist in nine states, and is not on the ballot in 19 states, but that's not enough.

In 2018 the Democrats managed to get the Greens kicked off the ballot in Montana. So the Democrats doubled-down in 2020 starting in Wisconsin.

A Democratic Party spokesperson filed a challenge against the Green Party petitions, claiming the change of address by Walker invalidated some of the petitions.

The hearing on the challenge before the state Elections Commission had all the trappings of a kangaroo court. The attorney for the Democratic challenger huddled with the Democratic chair of the Elections Commission to restrict the testimony of Green Party attorneys.

The Democratic challenge was upheld by the Commission and the signatures on those petitions were invalidated — conveniently enough to keep the Greens off the ballot.
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In Pennsylvania, the Democrats went to the Pennsylvania Supreme Court to remove Hawkins/Walker from the ballot. They were victorious on the flimsy technicality that the Greens did not submit signed filing papers in person but mailed them in.

You might be aware of the dirty tricks the Democratic Party in North Carolina has been using to get the Green Party off the ballot this year, but the Dems have been waging war on democracy for longer than that.
People are upset that the North Carolina Dems got copies of the Green Party petitions and went to signers and encouraged people to remove their signatures. But in fact that is exactly what the Dems did in 2020 to get the Green Party kicked off the ballot in Montana again!

So far the Libertarian Party has been most successful third party at surviving this onslaught, but they have their own self-inflicted problem. While Libertarians have long been in perfect agreement with the GOP on economic issues, they have at least separated themselves from the GOP on the culture war issues.

Libertarians have a long history of describing themselves as fiscal conservatives who are social liberals and arguing that the War on Drugs and the evangelical Christian Right have been terrible for the Republican Party and terrible for the conservative movement.

At least that was until recently. Now the Libertarian Party has become the MAGA wing of the GOP.

In July 28, 2017, Jeff Deist, the president of the Mises Institute, named for libertarian economist Ludwig von Mises, published a blog post arguing that “blood and soil and God and nation still matter to people. Libertarians ignore this at the risk of irrelevance.” The phrase “blood and soil” already had an unmistakable fascist overtone—but it took on an even more gruesome connotation two weeks after the post during the infamous Charlottesville Unite the Right Rally of 2017, where an anti-racist protester was killed. The white supremacists who tried to dominate the streets of Charlottesville chanted “blood and soil.” Several of the organizers of the Charlottesville rally identified as libertarians. In the wake of that event, Nicholas Sarwark, chair of the Libertarian Party, signed an open letter warning of the dangers of fascism. Arvin Vohra, vice chair of the Libertarian Party, wrote a post arguing that the “Mises Institute has been turned into a sales funnel for the White Nationalist branch of the Alt Right.”

The ensuing arguments over “blood and soil” lead to the creation of a Mises Caucus, which aimed to overthrow the pragmatic Gary Johnson wing of the party and adopt the incendiary culture war politics of the hard right.
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On May 29, at the Libertarian Party Convention in Reno, McArdle won the title of chair of the party’s national committee. This was a decisive victory for the Mises Caucus, which received the vote of 69 percent of delegates. The Mises Caucus is now the undisputed ruling faction of the party.

"Taking the Libertarian Party out as a competitive force will help consolidate the right-wing vote around the Republican Party."
- Jeet Heer

Liberty and the alt-right are incompatible.
On the other hand, if an extreme right-wing element undermining a fringe conservative political party sounds familiar, it should because Trump did this to the Reform Party.

Donald Trump says he’s never run for president before, but like much of what he says, that’s not quite true.

In 2000, he actively sought the Reform Party nomination, winning primaries in Michigan and California in the third party founded by Texas billionaire Ross Perot to fight NAFTA (North American Free Trade Act), and promote a balanced budget....
Trump left the race early citing infighting not “conducive to victory,” but there was more to the story. He had a “liquidity issue” (sounds familiar) and his campaign hinged on whether he sold his casino in Atlantic City.

Trump’s exit from the Reform Party race in February 2000 cleared the way for Patrick Buchanan, right-wing renegade from the GOP, to seize the nomination, which in turn led to the Reform Party’s eventual collapse.

While the Democrats are in-your-face at keeping the Greens off the ballot, the right-wing appears to take the more subtle strategy of undermining parties on the right from within.