Nnnnnnnnope. What stopped Bernie was certain states being allowed to bar independents from voting for democratic seats.
What is an oddity is the fact some states allow independents to be involved in choosing the candidate for a party. IMO it's only members of a party who should be choosing their candidate. It's pretty much how it works in every other country.
“The fundamental cause of the trouble is that in the modern world the stupid are cocksure while the intelligent are full of doubt.” - Bertrand Russell
"When the power of love overcomes the love of power, the world will know peace."