I can intend to write in Donald Duck because I believe there is a nationwide movement to elect a Disney character. Doesn't mean it isn't a stupid idea. 3rd party's don't work in our winner take all system. With no opportunity for coalition government, 3rd party's will always fail. Why do you think Ron Paul came back to the Republican party? He knew that without the GOP label his beliefs could never be advanced.
Donald Duck is a fictional character.
The Libertarian and Constitution Party are recognized alternative parties in the US.
There is absolutely not one time that the US Constitution uses the word “party” whether in the body, the bill of rights, or the other amendments.
There is no place at all that the US Constitution says “The US is a 2 Party System”.
Now THAT is fictional.