In the U.S. the two major parties work to keep third parties off the ballot and to create rules making it difficult for them to succeed. I can't cite chapter a

In the U.S. the two major parties work to keep third parties off the ballot and to create rules making it difficult for them to succeed. I can't cite chapter and verse, but I've seen stories about third parties being sued over every possible ballot application technicality, being excluded from debates, etc.