It looked like a mad moment of expansionism. Eight years ago, as part of a costly push into the digital age, the BBC set up a group of niche radio stations in a blizzard of canapés, cocktails and optimism. At the time critics said that the then director general, Greg Dyke, was leading an unaccountable exercise in empire-building funded by the taxpayers.

It did seem a bit of risk, even to those involved. Back in 2002, not many people had digital radios and televisions. By chance or design, BBC 6 Music, devoted to playing and supporting new and live music, has found a loyal listenership prepared to battle alongside the broadcasting unions to save it from closure.

As rumours of the threat to 6 Music grew, a rescue campaign was set up on Facebook by Jon and Tracy Morter, fresh from their success in promoting the extraordinary sales surge that saw Rage Against the Machine anointed as the Christmas No 1. Yesterday the Morters had more than 66,000 music fans on side and their list keeps growing. International stars such as David Bowie also began to speak out. Through his press company, Bowie stated: "6 Music keeps the spirit of broadcasters like John Peel alive and for new artists to lose this station would be a great shame."

The expected announcement this week of radical cuts that will include the closure of 6 Music is a desperate measure taken in adversity by Mark Thompson, the man now in Dyke's chair. In the current economic climate, the BBC fears it is about to come under serious attack, particularly if a Conservative government is elected in the spring.

The BBC Trust has asked Thompson to review the corporation's structure and his weak denial of a plan to axe 6 Music suggests the station will be one of the sacrificial lambs to prevent wider privatisation. The corporation promises that this is not the start of a comprehensive retreat from digital terrain, but just a "very hard look at our current activities and stopping doing some things that are not core to the BBC's mission". The planned cuts will allow £600m a year of the BBC's £3.6bn licence fee income to go towards "higher quality programming".

For DJs and music fans, the problem is best summed up by two remarks yesterday on the microblogging site Twitter. While one contributor emitted the cyber-wail "Nooooo. They can't shut BBC 6 Music", another responded: "whats all this about 6 music. never heard of it. is the 6 bit a typo?" Unfortunately, even today, when most homes can receive digital channels and radio, 6 Music has fewer than 700,000 listeners.

On 11 March 2002, the comedian and DJ Phill Jupitus put out the first show on a new station that had been codenamed "Network Y". It was the first such launch at the Beeb for 32 years. With its live sessions and idiosyncratic shows, 6 Music has attracted little national attention, although there was brief uproar in 2007 when controller Lesley Douglas changed the schedules to appeal to more women, saying that men had an intellectual approach to music listening, while women were more emotional. The ferocious reaction was an indication of just how passionate music fans can be.

James Murdoch, News Corporation's chairman and chief executive in Europe and Asia, accused the BBC at the Edinburgh Television Festival of having made an unfair "land grab" on the media market. But he may soon see the commercial sector – in the shape of Absolute Radio, the station formerly known as Virgin Radio – step up to buy 6 Music. Absolute's chief operating officer, Clive Dickens, said last week: "We would buy both the brand and the network, and we'd run it more efficiently."

For the music industry, the survival of a station like 6 is key. "I sincerely hope it doesn't fall down. It plays a lot of very exciting new music," Mike Smith, managing director of Columbia Records, said. "6 Music has been the first place that a lot of bands have played live sessions. It is one of the few places where the DJs actually play their own music and as a result it has a strong personality."

Smith's attitude is echoed by several of the DJs involved. Richard Bacon was one of the first to step out from the corporation line. "Here's my prediction: 6 Music will survive because of the scale but most importantly the passion of the backlash that's coming," he tweeted last week, while the breakfast show host, Shaun Keaveny, told listeners: "First of all, massive thanks to everyone who has shown their support, it's literally choking us up. Nobody could know the whole story, and we won't until something like 9 March. We hope it isn't true, of course."

Lauren Laverne, the arts presenter and former rock star, is another of the DJs who help define 6 Music's flavour, along with Stuart Maconie, Steve Lamacq, Jarvis Cocker and Elbow's Guy Garvey. Laverne also shared her feelings on Twitter. "Looks like I'm joining that Facebook group then," she wrote. "Boo, boo and thrice boo. That is all."

Considering what offbeat propositions 6 Music and its sister digital station, BBC Radio 7, originally seemed to be, it is surprising how on target they both proved, finding devoted listeners who say they cannot find the same content elsewhere. Radio 7, which also launched in 2002 and plays archive drama and comedy material as well as some new children's programmes, is the more popular of the two stations, with 884,000 tuning in at the end of last year. It will escape this round of cuts, but another digital station, BBC Asian Network, is in the firing line, along with two initiatives aimed at teenagers, Switch and Blast! Similarly, half the pages on the BBC website are likely to go, with a quarter of staff being axed. The corporation's publishing arm is also in danger of being sold off and spending on American imports could be cut by a quarter. Spending on sports rights is to be capped.

Each of these moves will provoke its own battles. Thompson is sailing into rough water whatever he does next, but last week's call from the National Audit Office for a "change of culture" at the BBC, coupled with news that the corporation's £1bn-plus refurbishment of Broadcasting House will be four years late and £110m over budget, is not a great place to start the voyage.