....But Martin Kettle has written a very good column indeed on the influence newspapers have on the opinions of the populace and the way that they vote .
The big error of politicians is to believe that newspapers change the way people vote.(...)Newspapers exist for many purposes. An important one is to sell papers. By and large they aim to satisfy their readers, not alienate them..(....) The Ipsos Mori evidence actually suggests the very opposite. It sits comfortably with current fashionable notions of voting as a cultural choice rather than as a choice based on supposed rational self-interest. People choose a newspaper that suits and reflects them culturally. One of the ways it reflects them is political stance - though it is by no means the only one, as politicians like to believe.
Quite simply, newspapers reflect the already extant thoughts, opinions and prejudices of their readers rather than shape them: that's why people buy a particular newspaper in the first place. The academic research  does seem to back this up (at least on the grand scale, there is of course a little bit of movement, as Kettle says, around the margins):
Consistent with their theory that media bias is mainly driven by customer tastes, they find that reader ideology explains significantly more of the variation in media bias than the identity of its owner. This finding holds up even when they take account of the possibility of reverse causality. Places with more churchgoers (a trait unlikely to be affected by newspaper bias) tend to have more right-wing newspapers. Conversely, cities with fewer churchgoers tend to have more left-wing newspapers.
Now this isn't really all that new, it's a confirmation of something that many have thought for some time. But what does make it interesting is that we might finally be able to put to bed this contention of Polly Toynbee's :
The malevelovence of the media is underestimated by social researchers. Historians leave its deformations to footnotes. But it helps explain why an ever more prosperous, secure and healthy country is so unhappy and fearful.
Here's an example of its influence: an overwhelmingly rightwing bias helps explain why Eurobarometer finds the British the least sympathetic of EU nations towards the poor, more likely to blame them for laziness.
Of course, we have to translate Polly's "rightwing bias" to "vaguely not social democratic" given her own stance on the political spectrum but once we've done that we can go on to point out the error in her thinking.
We're not all raving right wingers (ie, not social democrats) because we've been mesmerised by the press into not understanding how much better off we would be if ruled by La Toynbee's latest enthusiasms. The British press is ravingly right wing (ie not social democrat) because the British people are ravingly right wing (ie, not social democrats) and thus unlikely to be enthused by whatever is today's arrogantly paternalist plan and thus there's no way to sell newspapers trying to tell people about it.