As a foreign-born U.S. citizen, Musk cannot run for president but he can support third-party candidates, who can put themselves on the ballot in every state, if they have enough signatures to support their bid. It is rare for third-party candidates to break through significantly.

Some people think billionaire Elon Musk 'wants to be US President' as he announced that his new America Party has been "formed" – but there's a reason he can't be

Here's what it would take for Elon Musk to launch a third-party effort to represent what he called "the 80% in the middle."