Cambridge Analytica are relevant to LeaveEU, Darren Grimes is relvant
A large donation of campaign money was donated to Darren Grimes 'social media campaigner' who passed that money on to Aggregate IQ -- AggregateIQ had just been a short-term “contractor” to Cambridge Analytica.
Robert Mercer of Cambridge Analytica is good friends with Nigel Farage, who does seem to spend a lot of time in the states these days... with these Trump aides. "Andy Wigmore, Leave.EU’s communications director, told me that it was Mercer who had directed his company, Cambridge Analytica, to “help” the Leave campaign."
Cambridge Analytica has data points such as social media, financial, residential, employment and connections on many millions of people. They can target individuals using tracking in browsers as well as social media. They can understand who are vulnerable and target them. They can influence voters with online targeting and media targeting to smear opposition to encourage voters to stay at home. The Guardian has done some top notch investigative journalism on this.