Her attempts to become a pop star have all but foundered and not even a pair of Daisy Duke shorts (sported in the 2005 film The Dukes of Hazzard) could resuscitate an acting career beset by straight-to-DVD flops. Yet Jessica Simpson, the blonde staple of gossip magazines and reality TV, is now on the way to commanding a fashion empire worth $1bn.
In the past year the 30-year-old Texan's lines of jeans, swimwear, shoes, lingerie, watches and fragrances have taken sales of $750m (£477m) – or almost 10 times the amount her last film took at the box office.
Simpson has spent a life in the shadows of stars such as Britney Spears and Christina Aguilera, who started with highly sought-after presenter jobs on The Mickey Mouse Club as teenagers. Now Simpson, who failed the audition for the Disney gig, may yet outstrip them both in earnings.
She followed that rejection with an initially successful singing career – and a failed attempt to make it in Hollywood – but hard times have not dented her ambition. She has said of her billion-dollar sideline: "I'm hoping the business will outlive me. I plan on making this a business model based on Ralph Lauren or a Michael Kors-type of line."
Few in America – her lines are less well-known in Britain – would doubt her. Simpson's dresses, which sell at around the £100 mark, are popular with teenage girls as well as grown-ups. She has more than 3 million followers on Twitter and more than 600 customers recently queued to see her make an in-store appearance.
"Celebrities often try to cash in on the cachet of their personality to create a brand," says Karl McKeever, brand director at Visual Thinking. "Consumers want to participate in a certain lifestyle and buying [the celebrities'] clothes allows them to gain entry to a special club. They inherently want to be associated with certain celebrities."
Simpson, despite her many gaffes, including once asking on camera whether "chicken of the sea" tuna was, in fact, chicken, has gauged a mood in the States. The public love her for her failures, thereby creating her success. She has overcome several set-backs professionally, a failed marriage and reams of column inches detailing her every physical fluctuation. Simpson is seen as human and likeable – not to mention curvy.
Her clothes are girlish and glitzy, feminine and frilly, but nevertheless wholesome. They're the sort of thing 16-year-olds dream about wearing to the prom, and that older customers buy because they want to look 16 again. There's a huge market for this type of non-threatening, easily accessible, "safe" clothing, and Simpson's prices carefully straddle the boundary between premium and "masstige" – they're affordable treats for some, and aspirational must-haves for others.
Simpson is the most successful among a growing crew of celebrities keen to explore their sartorial sides – we're used to seeing clothing endorsed, and supposedly designed, by famous faces. Usually though, they are personalities more readily associated with fashion, such as supermodel Kate Moss, style icon Alexa Chung or the anti-fashion rock star Beth Ditto.
But celebrity lines in America are much more personality-led: actress Jennifer Lopez and her husband Marc Anthony are launching an accessories collection, while Brad and Angelina have already created a jewellery range. Similarly, Simpson has no ties to the fashion industry as such, and is perhaps all the more popular for it; her dresses are not aimed at those who follow catwalk trends. "All these celebrities have in common is the fact that they have latched on to a popular movement of a time," adds Mr McKeever. "The less imaginative consumer is happy to go along with it."
With rocketing sales figures and the imminent addition of a new sportswear line to the range, Jessica Simpson (the clothing) is close to hitting the $1bn mark. But Simpson is far from entering the Forbes Rich List just yet. She sold the master licence to her name – that is, the right to use it on products – in 2005 (about the same time she took those denim shorts off) to the Camuto Group for $15m. Simpson receives royalties for the range, which she is said to have taken an active involvement in, but her annual income is estimated by the people at Forbes to be more in the region of $20m. So she's not quite a fashion mogul yet.
"If the products are decent in themselves, they're even more desirable with a name attached," says Mr McKeever. "But it could also be a curious anti-branding movement – the joke factor, because of a certain kitchness. But really, the joke's on you – you're still spending your money."