The Brexit party used simple messaging, an active social media presence and a “overwhelmingly negative” attack to win the online battle before the European elections, according to a new analysis of the campaign.

Nigel Farage’s party accounted for 51% of all shared content on Facebook and Twitter during the campaign, despite only producing 13% of the content. The analysis, by the 89up digital agency, said the “scale of their success went beyond what we were expecting”.

Meanwhile, Change UK, made up of pro-Remain former Labour and Tory MPs, were the losers of the internet campaign. Despite spending more than £100,000 on 1,000 Facebook ads in the week before the vote, Change UK generated 1.1% of all shares on the platform – fewer than any other UK-wide party.

The election saw the Brexit party top the polls, with 31.6% of the overall vote. Having made an impression in the polls after its launch, Change UK secured just 3.4% of the vote. The best performing pro-Remain party was the Lib Dems, who finished second with 20.3%.

The analysis looked at each party’s impact on Facebook and Twitter, their top-performing content, and the impact of their party leaders. The analysis found the Brexit party generated more than 45 times as many shares through “simpler, stronger messaging and a deeper understanding of their audience”. The campaign was “overwhelmingly negative”, focused 39% of all ads on attacking Labour and prioritised older Facebook users in England rather than 18-24-year-olds, or residents of Scotland and Northern Ireland.

The analysis also identified dozens of pro-Brexit party accounts with a “high likelihood of being inauthentic”. The accounts were all created relatively recently, had Brexit party profile pictures, tweeted dozens to hundreds of times a day, and posted almost exclusively about Brexit.

From posts made between 5 April and the election, The Brexit party made 212 to Change UK’s 62 posts. It received 325,900 shares, compared to Change UK’s 7,200 shares. Change UK’s messaging was criticised as complex, suggesting that a vote for them would lead to a second referendum, which would in turn allow the British public to have a final say. The Brexit party’s posts were more direct and emotionally charged, compelling followers to “save democracy, support Brexit”, or help Britain avoid humiliation. The Brexit party’s Facebook posts were an average of 19 words long. Change UK’s were 71 – more than three times longer.

In 212 posts, the Brexit party avoided talk of immigration or the benefits of Brexit, focusing instead on the idea that cancelling Brexit would be undemocratic, or as they’d put it: “This isn’t about left or right, it’s about right and wrong.”

Mike Harris, the chief executive of 89up, said: “The Brexit party’s social media campaign is a lesson for the pro-Remain parties who were significantly less effective during the European elections. The Brexit party spent less than a tenth of Change UK, the Greens and the Liberal Democrats in the last week before the elections, but had significantly more reach and engagement with the public.

“While some of this was potentially due to inauthentic bot activity, a lot was due to the clarity and simplicity of their messaging which the Remain parties must learn from.”