The Conservative party is pursuing an “ostrich strategy” on Facebook, spending almost all of its ad budget since the beginning of the year in constituencies that were once marginal but are now looking more like surefire losses, Guardian analysis shows. The strategy is known within the party as the “80/20” approach, in which it focuses all its spending on the 80 seats it came closest to losing in 2019 and the 20 seats it came closest to winning. Ad spending reports on Facebook show that these constituencies are exactly where the party is funnelling its money. More than half of the party’s spending on the social network since January has gone to its 80 tightest seats, or to seats it does not hold at all. The Guardian collected every advert run on Facebook or Instagram since the beginning of the year that mentions a Conservative prospective parliamentary candidate (PPC) by name, and that was paid for by either the Conservative party or the Scottish Conservative and Unionist party. The social network does not report absolute spending, but gives an approximation, showing that at least £100,000 was spent on such adverts in the last five months. However, the distribution of the spend suggests that the party’s campaigning has not yet caught up with the reality of its position in the polls. Almost a fifth of the budget was spent on seats that the party would lose with a swing of at least 3% against it in July, including Bury North, which the party won by just 105 votes in 2019, and Burnley, which it gained from Labour by a majority of 1,352. The third largest recipient of funds from the central party was Chipping Barnet, where the former environment secretary Theresa Villiers won in 2019 with a majority of just 2.1%. Based on that year’s results, the seat is the 47th most marginal. The party even devoted funding to adverts in seats it doesn’t hold. The Scottish Conservatives spent 5% of the total national-level funding on a range of seats held by the SNP, including East Renfrewshire, where the SNP majority is 5,400, and Angus and Perthshire Glens, a new constituency formed from a cluster of five SNP-held seats. Plans for an “80/20” election strategy were first reported in January 2023, aimed at turning around the party’s polling deficit, which saw it reliably trailing Labour by around 20 percentage points. The strategy was based in part on an assumption that the polls would narrow as the election drew closer, with the hope that targeting some seats held by opposition parties could pick off enough gains to offset losses elsewhere due to a realignment in UK politics. In fact, the polling margin has remained remarkably stable since last year, the most noticeable long-term trend being an increase in the share of the vote for Reform, largely at the expense of the Conservatives. Labour currently stands more than 21 points ahead of the Conservative party, according to the Guardian’s polling tracker. If that swing is replicated nationally, then seats like those of Greg Hands in Chelsea and Fulham, Jeremy Hunt’s in Godalming and Ash, and Connor Donnithorne in Camborne, Redruth and Hayle – all of which received national funding for social media advertising – would be all but impossible to defend. With the election campaign in full swing, and more than 100 Tory PPCs still to go through selection, the party is likely to increase its spending on Facebook in the coming weeks. Some, though, has been wasted, no matter the result: adverts supporting Andrea Leadsom and Michael Gove won’t help secure re-election for the pair, who have confirmed that they are standing down. Additional reporting by Pamela Duncan.