Influencers are everywhere you look these days – including America’s campaign trail. Some 200 social media stars attended the Democratic National Convention in August, where they were entertained at lavish parties and on boat trips. A few even got to chat with Kamala Harris. Donald Trump has likewise given interviews to influencer bros such as Logan Paul and Theo Von, aiming to appeal to their followers.

Politicians are not the only ones to have spotted the growing sway of social-media stars. Over the past five years, American companies have roughly tripled the amount of marketing spend they lavish annually on influencers, to $US7 billion, according to research firm eMarketer. Influencer marketing is part of every big campaign nowadays, says Mark Read, the boss of WPP, which owns advertising agencies such as Ogilvy and Mindshare. Walmart, a retail giant, has worked with TikTok stars Dixie and Charli D’Amelio. Louis Vuitton, a luxury brand, has run campaigns with Emma Chamberlain, a YouTuber.

Siblings Dixie, left, and Charli D’Amelio, rank among the most followed people on TikTok.Credit: Evan Agostini/Invision/AP

Goldman Sachs bank estimates that as of last year there were more than 50 million influencers globally, from fashionistas on Instagram and comedians on TikTok to gamers on YouTube. It reckons that their ranks are swelling by between 10 per cent and 20 per cent annually. Some influencers view the work as a pastime; others aspire to make it their vocation, lured by stories of superstars making tens of thousands of dollars for a post and harnessing their legions of followers to launch brands of their own. In the United States, 57 per cent of Gen Zs would like to be a social media influencer, according to........

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