You might well lose your money, though. In the eight weeks since her solo album Schizophonic was released, it has plummeted from its initial chart placing - No 4 - to a sorry 53. And in May, Halliwell's debut single "Look At Me" charted at No 2 - impressive for anyone else, but a failure after all the publicity that had paved its way. It's been just 14 months since Halliwell's less than amicable divorce from the Spice Girls. So soon after a period when everything she touched turned to ginger, detractors are saying that she is on her 15th minute of fame.
There's evidence enough if you want to make that case. Releasing "Look At Me" in the same week as a new Boyzone single was a tactical error, and it was, apparently, Halliwell's decision. "She wanted the challenge," said Chris Briggs, an EMI executive. Then came the "Geri sacks manager" stories. In the month between the releases of "Look At Me" and Schizophonic, Halliwell and Lisa Anderson "agreed to conclude their business relationship", to quote their joint statement. The tabloids were quick to attribute the split to the under-performance of "Look At Me".
"The album's not a hit, it's gone," says one industry insider who, like almost everyone I spoke to for this article, didn't want to be named. "And EMI spent a phenomenal amount on promoting it. What with the video, posters and retail deals, it's got to be a couple of million. It's more than I can remember from the launch of any other record." He believes the album was over-hyped. "But they couldn't have done it any other way. After all the money the Spice Girls made for EMI, the company had to be seen to be making a splash. They couldn't risk her going elsewhere. Whether they can salvage the album with the second single is debatable. Personally, I doubt it."
It is almost inconceivable that Halliwell could be on the scrap heap so soon after the Spice Girls were on top of the world. The group sold a mind-boggling 39 million albums, and Halliwell's sloganising was a significant factor. Then again, her former Girl-friends have been as swift as anyone to consign the Ginger Age to history. In the September issue of Q magazine, Mel C deems Halliwell's album "not great, but all right". "I find it difficult to take her as a serious artist," says Sporty, unsportingly. "For me, she's just cotton wool. She's not a talented musician, and she's not a very strong singer ... She's a great celebrity, but musically, it doesn't come from here [the heart]. It's just hollow." Mel G has been just as sisterly. Asked why Halliwell quit, Scary said: "She wasn't one of the most best singers [sic] or the best dancers, but I'm sure that wasn't the whole reason why she left ... I suppose it's a bit annoying when all you're seen for is your lips and your boobs."
This carefully measured pipette of poison was squeezed out in a Spice Girls documentary televised the night before Schizophonic's release. In the film, the Fad Four strutted around America, fulfilling professional commitments and keeping success in perspective. In contrast, Channel 4's recent documentary about Halliwell's post-Spice life was painful viewing. Molly Dineen depicted her drifting miles from reality, reading self-help books and writing to Prince Charles. Surrounded by employees, Halliwell complained of debilitating loneliness. And she seemed to have no clue what she wanted to do with her life. She just knew she wanted to stay famous.
The documentary, repeated just a few weeks later, would hardly have encouraged young admirers to buy a summery pop record. Ginger Spice had embodied fun and confidence; she wasn't the sober, grey-suited UN ambassador or the tearful, directionless waif seen on Channel 4.
"EMI are launching a second phase in Geri's career and they're trying to get beyond her core market of tweeny pop fans," says one media analyst. "The album has a bit of Latin, a bit of disco, it goes right across the board. They've gone for a fairly mainstream adult market, and that's quite an intangible one. It's only really the Corrs who are doing well in it. The trouble so far is the mixed messages she's sending out. Is she an ambassador, a mainstream pop star, or is she going for the gay market? That's something they've got to decide."
Halliwell's public relations company, run by Matthew Freud, is keen to point out that if Schizophonic is, so far, a flop in Britain, it has sold 1.3 million copies worldwide. "EMI are backing the album really heavily as a long-term project," says Freud Communications' Simon Jones. "There's going to be another single in late autumn, and it's going to be promoted throughout the year. It's not over yet."
To an extent, this is PR bravado. And Jones's subsequent insistence that Halliwell is a new artist who shouldn't be compared with the Spice Girls is surely disingenuous. (A fax of her solo sales statistics concludes with the following tart detail: "The single `Look At Me' has outsold both of Mel G's solo releases and Mel C's duet with Bryan Adams in the UK.") On the other hand, the continued support of the firm is in itself some kind of recommendation. "Matthew Freud is very important and very powerful," comments one insider. "He dumps losers pretty fast and he hasn't dumped Geri."
And Halliwell still has the teen pop bible Smash Hits on her side. "She remains a source of intrigue and fascination and affection for a lot of our readers," says John McKay, the editor. "I've had a lot of mail saying, `Will you pass this on to Geri? She's inspirational'. She's like a refuellable lighter - the flame won't go out."
Remember, too, that Halliwell is a woman of many projects. Her autobiography, If Only, will be out in October. Its publishers were unable to provide any information about the book, but a source close to the Spice Girls has seen it. "It's `me, me, me'. It says that she was responsible for everything, that the Girls' success was all down to her ideas. But it's written in a very childish style. The only way Transworld can recoup their advance is by doing a massive serialisation."
If Only is not Halliwell's first literary venture. "She wrote a book while she was still with the Spice Girls," says - yes - an insider. "It was a semi-autobiographical thing about this kid from a tough background who did some things in her past which she regrets and then becomes a star. It ended with a Marilyn Monroe sort of thing: her meeting Clinton and then topping herself. But it never saw the light of day."
In most conversations with Geri-watchers, the name Robbie Williams crops up. Like Halliwell, he walked out of a wildly successful five-piece British pop group. He signed to EMI, the same label as Halliwell. And Williams' debut LP, Life Thru a Lens, didn't get to No 1 until it had been out for 28 weeks. It took the release of the album's fourth single, "Angels", to push Life Thru a Lens past a meagre 33,000 sales. EMI are now hoping that one of Halliwell's singles will do an "Angels" - or a mini-"Angels", at least. Maybe "Mi Chico Latino" will be what they're waiting for. Released in a week's time, it's already a fixture on The Box, the cable music channel which is challenging Radio 1 as a gauge of pre-teen tastes.
"Geri's not dissimilar to Robbie," says one of Halliwell's associates. "If you speak to either of them, sometimes you think, `You're a stupid, whingeing pain in the neck.' Other times you think, 'God you are smart.' You can't just cast her as a stupid pawn. She has a pretty acute understanding of market shifts and movements and she does know what the game is about."
This is the kind of remark that's usually said about Madonna. "It's true. Like Madonna she's a manipulator and a manipulatee. Madonna isn't much of a singer or a dancer, but her genius is as a voracious consumer of other people's styles, and Geri has some of that. She can be a real pro in the way that Madonna is. Sometimes she hits, sometimes she misses, but her instincts are often spot on."
But even these comparisons don't tell the whole story. Few would deny that Halliwell has weaknesses that Williams and Madonna don't. It may all be relative, but Halliwell is a worse singer than either and is considerably less skilled at entertaining a crowd. But as Mel C says, Halliwell is "a great celebrity". Perhaps it would be more illuminating to think of her as a glamorous Frankenstein's monster, sewn together from parts of Robbie Williams, Madonna, Melinda Messenger and Princess Diana.
It's hard to say what Halliwell has that a thousand other stage-school girls don't. "She's not Brain of Britain, but she's incredibly streetwise," offers a friend. "She's a fighter." But what does that mean? Try to pinpoint Halliwell's abilities and you're left fumbling with "ambition" and "drive" and "surviving" and "understanding how the system works". If all else fails, she can always teach a course in media studies.
`Mi Chico Latino' is released on 16 August