Blogs are a spin doctor's worst nightmare come true - and then some. It would be understandable if political parties regarded them as uncontrolled, uncontrollable and sometimes downright troublesome. But if they did, they would be missing a huge opportunity to market their message without the filter of mainstream media reportage and comment. The political party that can harness blogs to its cause is the one that will win the internet campaigning war.

Last week the Lib Dems held a fringe reception for bloggers. At the Conservative conference, 'blog surgeries' will be held for those who want to know what it entails. I will be one of the Blog Doctors on call. And what is the Labour Party doing for bloggers this week? Virtually nothing. Labour understands only too well that their media operations cannot control blogging. They are offering all their members a blog, but these will be read only by other party members, and comments on them. Typical.

Political party memberships are declining in part because parties have no idea how to communicate with members. Mailshots are expensive, monthly magazines far too costly and, despite spending large amounts of money on websites, none of the parties has really 'got' interactivity. Party websites speak 'at' people rather than to them. It is no coincidence that the slightly subversive ConservativeHome.com and my blog both get far more visitors and hits than the official Tory party website.

The trouble is, most politicians see all the dangerous downsides of blogging but rarely the benefits. There are some notable exceptions, such as LibDem MP Lynne Featherstone, Labour's Tom Watson and Tory Ed Vaizey, but they are three of only about a dozen.

A few weeks ago I received an email from a 22-year-old: 'I don't buy this line that "young people are not interested in politics". We are, although it has to be presented in a manner in which young people who have grown up with the internet feel is relevant to them. A young person is more likely to access something on YouTube than watch the TV. We don't watch the 6 O'clock News on BBC1; we have the RSS feeds of numerous websites/blogs in our RSS readers. If the Tory party "get" this concept and harness it, they will be well on their way to mobilising a significant number of young people to vote for them.'

To me, that young man encapsulates the problems facing the mainstream media. Advertisers are flooding to the web from newspapers. Young people either do not read daily newspapers, or expect to pick them up for free . Broadcast news bulletins are becoming less popular as people get their news quotient from the internet. Just as satellite TV threatened the hegemony of terrestrial TV channels, now internet TV threatens to do the same.

Neither have MPs understood podcasting or videocasting. It's something they feel they ought to do but none of them quite knows why or feels the need to develop a strategy. Instead, their websites carry worthy speeches and press releases that fail to energise and engage. The party that changes its ways will, as my young correspondent said, reap the electoral reward.