The Daily Mail and the Sun are – what's the polite term? – bricking it at the thought that the Lib Dem surge could result in the party making a major breakthrough in this election. Ever since Nick Clegg's victory in that debate six days ago, the rightwing press, much like the Tory party, has been utterly paralysed, unsure whether to launch a full-tilt attack on the Lib Dems, or to patronise the party's surge as the teenage tantrum of an electorate who should jolly well just grow up.

And they're still confused. The Daily Mail's editorial today is the funniest: truly, it is quite genuinely (and unintentionally) hilarious. The "only explanation" for the Lib Dems' rise, it imperiously states, is that "the public, disgusted by the near moral bankruptcy of the last parliament, is looking for revenge".

Those of us who read the Mail are familiar with its leader writers' shrill moralising. What's more telling is their desperation today to attack the Lib Dems, flinging whatever mud they can dig up on the presumption that some of it will stick. The Mail's list of charges against the Lib Dems is so hyped-up as to defy their readers' intelligence.

For instance, we are told that Lib Dem MPs were the "worst expenses offenders" – in spite of the fact that not a single Lib Dem MP was connected with the most serious abuses of "flipping" their second homes for capital gain, nor claiming for phantom mortgages. The Mail conveniently ignores the Lib Dems' determined efforts over many years to clean up politics – such as giving the public the right to sack corrupt MPs, putting a cap on political donations, and clamping down on lobbying – in the teeth of Labour and Conservative opposition.

"Fisking" a Daily Mail editorial is, I fully realise, an utterly futile activity. And perhaps we can forgive the paper for treating a political party's surge warily. After all, the last time the Mail advocated breaking the mould of British politics they sided with the British fascists and Hitler.

What really worries the Mail and Murdoch about the Lib Dem poll ratings is this: they understand Clegg's party is a direct threat to the cosy status quo with which they are so comfortable. Don't take my word for it: the former Sun editor David Yelland made the point quite explicitly on these very pages just a couple of days ago in his explosive article that Nick Clegg's rise could lock Murdoch and the media elite out of UK politics.

Will the tabloids' full-frontal assault work? We will see. I think its utter and complete over-the-topness is far too transparent, and that fair-minded voters will see it for what it is: a knee-jerk reflex from a paper out-of-step with the times. It's perhaps significant that one of the top-rated comments on the Mail's website from one of its readers asks simply: "Do Tory party central office write all of this paper?"

Of course newspapers matter, and I would much rather the Mail and Sun were offering their readers proper news rather than rightwing agitprop. But they no longer matter as much: most of the public take in their information from broadcast media, which is obliged by law to be impartial. And the staggering success of the unofficial Lib Dem Facebook group – with 120,000-plus members, now far bigger than the Labour and Tory fan-groups combined – demonstrates the power of the internet to mobilise voters who scorn the rightwing press's attempts to dictate the news agenda.

The Lib Dem rise in support is about more than just a rejection of the ways of the two old parties that have ruled this country for 65 years. It is also a rejection of the age-old stitch-up between the vested interests of traditional politics, the media, big business and trade unions that has so often left the British public short-changed.

This is about the British people taking a long hard look at their elites, putting their foot down and saying: enough's enough. This is, above all, a very British insurgency.