Supporters of a controversial California proposal to implement a one-time tax on billionaires say they have enough signatures to qualify it for the November ballot.

Bernie Sanders has traveled to Los Angeles to kick off a campaign for a proposed “billionaires tax” that has set off an uproar in the Silicon Valley and led to divisions among Democrats.

A billionaire-backed proposal to build an eco-friendly California city from scratch is off to a bumpy start to put their idea before voters this November.