... or a book... or a cowpad of a book. You can read up on it here, if you're that way inclined.
Rebekah Mercer is a billionaire heiress and daughter of Robert Mercer. Robert is best known in the UK for maybe having decided, possibly illegally, the fate of the Brexit referendum:
Mercer was an activist in the campaign for the United Kingdom to end its membership of the European Union, also known as Brexit. Andy Wigmore, communications director of Leave.EU, said that Mercer donated the services of data analytics firm Cambridge Analytica to Nigel Farage, the head of the United Kingdom Independence Party (UKIP). The firm was able to advise Leave.EU through its ability to harvest data from people's Facebook profiles in order to target them with individualized persuasive messages to vote for Brexit. It's been reported that Cambridge Analytica also has undisclosed links to Canadian digital firm AggregateIQ, which also played a pivotal role in Dominic Cummings' VoteLeave campaign, where he delivered an estimated one billion individually curated targeted adverts to voters in the lead up to the Brexit referendum, in contravention of established voting rules. Both VoteLeave and Leave.EU did not inform the UK electoral commission of the donation despite the fact that a law demands that all donations valued over £7,500 must be reported. In 2018, the Electoral Commission found the VoteLeave campaign guilty of breaking electoral law.
So a foreign (the Mercers are thoroughbred Americans) agent strongly influenced a momentous British election. Imagine the howls of American indignation if such a thing was foisted on one of their elections (think Russiagate)?