At the risk of ruining his career, I would like for the second time this campaign to commend the work of Channel 4 political editor Gary Gibbon.

He is one of the few remaining political reporters who is interested in politics as opposed to politics as a source of sub-showbiz, processology and gossip.

The reason for my latest salute is his blog of yesterday which explained in part the mystery of why the instant polls on TV debates seemed so dissonant with what actually happened.

The idea that ‘Cameron won’ the third debate, thanks in part to the ‘unstoppable momentum’ strategy of DC’s many media tummyticklers was set largely because of the polls.

Now when you hear a poll has been conducted you might assume that they are polling a cross section of the public. Not so, Gary revealed.

The YouGov poll, for example, one of the earliest, was weighted to match what the pollsters believed would be the profile of the audience. So they included more prosperous voters than the national profile, more broadsheet as opposed to tabloid readers, and more older people. All of these groups tend to be more conservative.

ComRes do not weight according to imagined viewership but according to what they call voting population profile. The sample watched on Thursday lined up as follows.

Con 35, Labour 24, LibDem 36.

Now look at how they voted in terms of who ‘won’ the debate. Cameron 35 Brown 26 Clegg 33.

Get the picture? Indeed, based on that you could argue that GB ‘won’ (as indeed in my view he did) as he was the only one to score above his party rating. But in a campaign riddled with dishonest and disingenuous media reporting, this is the latest example. As I know from the mass of interviews I and other Labour people did in the ‘spin room’ after the debates, the polls are presented by the media, instantly, as snap judgements of the population. They are anything but. They are skewed. Yet I have yet to see or hear any caveat attached to them in the public presentation. Until Gary’s blog.

I don’t doubt a fair few politically interested Channel 4 viewers and others will see his blog. But what a shame the majority are unaware of the bent reporting of these ‘polls’ that ‘gave the debate’ to not so Wonderboy Dave.

It all confirms me in my belief that huge numbers remain undecided and they are the people Labour now has to reach out to in showing that the fight of the next few days really is a fight for Britain’s future.

** Buy The Blair Years online and raise cash for Labour http://www.alastaircampbell.org/bookshop.php.