The problem with the leave campaign is that everyone involved in it is such a massive bellend
Lots of people have already made their mind up but when undecided look at the type of people at the forefront of Leave they can't help voting Remain
Obviously every angry, ignorant racist will vote Leave too - do ordinary people want to be associated with that?
(obviously not everyone who votes Leave is an angry, ignorant racist - some will have good reasons to vote that way)