Stephen Glover: It wasn't The Sun wot won it for Cameron

Media Studies: Both Cameron and Osborne have bent the knee to the Murdoch Empire

Throughout the summer and autumn of 2009 the Tories were far ahead of Labour in the opinion polls. In July The Guardian's ICM poll put them on 41 per cent and Labour on 27 per cent. By September they had advanced to 43 per cent, and in October they stood at 44 per cent. Some pundits predicted a landslide.

And yet, as we know, David Cameron did not win the general election in May 2010. The Tories got 36.1 per cent of the vote. We will all have our differing interpretations. I happen to believe they presented too vague a prospectus. At all events, they did not do as well as might have been expected against a very unpopular Prime Minister and a discredited Labour Party. It is also impossible to ignore the fact that from the moment The Sun took up the Conservative cause – at the beginning of October 2009 – Mr Cameron's fortunes began to decline.

I do not suggest any causal link. What is undeniable, though, is that the fervent support given to the Tories by the Murdoch tabloid, as well as its denigration of Gordon Brown, failed to win them the election.

That is not to say they did not perform better with the support of The Sun than they might have done without. According to Ipsos Mori, there was a 13.5 per cent Labour to Conservative swing among Sun readers compared with a national swing of 5 per cent among all newspaper readers. On the other hand, this swing was 7 per cent among social grades C2 and DE, which make up a high proportion of its readers. It is also noteworthy that there was a 10 per cent Lab-Con swing among readers of the Daily Star, which took little interest in the election and offered no party endorsement.

On this evidence, The Sun may have delivered Mr Cameron some extra votes but by no means enough to affect the outcome. And the question which he and his advisers should be asking themselves is whether they did not greatly exaggerate the potential benefit of having the support of the Murdoch press. The costs of Mr Cameron's abasement in front of Rupert Murdoch surely far outweigh the benefits. His premiership will be undermined by public inquiries and continuing allegations arising from his appointment of ex-News of the World editor Andy Coulson, his obsessive courting of Rupert Murdoch, and his befriending of Rebekah Brooks.

It was not only Mr Cameron who miscalculated. In her evidence in front of the Commons Culture, Media and Port Committee last week, Mrs Brooks reminded us that it was George Osborne who pushed for Mr Coulson's appointment. I am also told that at the Chancellor's 40th birthday party, only two months ago, Mrs Brooks and James Murdoch were among a relatively small number of guests. Both Cameron and Osborne have bent the knee to the Murdoch Empire, and for the most part unnecessarily so.

Who else is guilty of phone hacking?

There is much talk of "contagion" over the phone-hacking scandal spreading to other newspapers. As a member of the Commons Culture, Media and Sport Committee interrogating the Murdochs last week, Tory MP Louise Mensch cited a report published by the Information Commissioner in 2006 which revealed that three Associated Newspaper titles (the Daily Mail, Mail on Sunday and Evening Standard, then wholly owned by Associated) had between them used a private investigator on more than 1,300 occasions.

Her apparent implication was that these and other titles may have been involved in phone hacking. What's the evidence? In 2003, staff of the Information Commissioner descended on the offices of a private investigator called Steve Whittamore. The evidence they uncovered was published in the 2006 report. Interestingly, whereas the Mail allegedly used the services of Mr Whittamore 952 times, The Sun did so on only 24 occasions. The Observer chalked up 103 transactions, which, as it is a once-a-week title, equates to more than 600 for a daily newspaper. The Independent and Telegraph titles do not feature on the list.

What does this tell us? Mr Whittamore was one among perhaps a half a dozen investigators then employed by national newspapers. This list therefore reflects those newspapers which used him and his associates. It seems highly likely that The Sun hired other private investigators. There is also no proof one way or another that any of these transactions involved phone hacking. Paul Dacre, editor-in-chief of AssociatedNewspapers, must have believed he was on solid ground when he told a parliamentary committee last week that the Mail had never published a story based on phone hacking.

The inquiry lacks red-top experience

I am sure the six people appointed by Mr Cameron to sit on Lord Justice Leveson's inquiry into press ethics are fine individuals, but there seems to be a lack of political balance and, in some cases, experience of the press. Only George Jones, ex-political editor of The Daily Telegraph, is obviously of the centre-right, though I have no knowledge of the political leanings of Sir Paul Scott-Lee, former chief constable of the West Midlands. Sir David Bell is chairman of the Media Standards Trust, which has often been critical of the popular press. Shami Chakrabarti, director of Liberty, is said to want statutory regulation of newspapers. There are no ex-editors, or anyone who has ever worked for a national tabloid. A more representative, high-powered and knowledgeable tribunal would have carried more conviction.

s.glover@independent.co.uk