Robert F. Kennedy, Jr., will hold a press conference in Phoenix, Arizona, on Friday, August 23, to discuss his campaign. There is some expectation that he will withdraw. The conference is at 2 p.m. eastern time.
If he does withdraw, he is free to leave his name on state ballots, or he is free to ask the states to remove his name.
Ross Perot withdrew on July 17, 1992, but he did not ask any state to remove his name from the ballot. In fact he asked them not to remove him. He re-entered the race on October 1, 1992, and appeared on the ballot in every state.
There have been presidential candidates on the ballot who had never even asked to be on the ballot, but because other persons or parties put them on the ballot, and the candidate did not ask to be removed, the name appeared on the ballot. Examples are Arkansas Governor Orval Faubus in 1960, General Douglas MacArthur in 1952, Senator Harry Byrd in 1956, and Ron Paul in 2008.