This newspaper is independent, as its name subtly hints, but its columnists are not. And so, knowing that this can be of no interest to anyone, I declare that I will be voting Labour for the first time since reluctantly overcoming my feelings about Tony Blair and his “project” to do so in 1997.

When I mentioned this intention to my father the other day, he questioned it with the most lethal three-syllable rebuttal in recent political history: “But Ed Balls…” I know, I know, I muttered, but we look to the positives. And what, he wondered, might those be?

Of the six or seven points that came to mind, I mention only two. One is a friend’s answer when her small son asked why she will be voting Labour: they care more about the disabled. This may seem a reduction of a complex process to a childishly simplistic argument (the boy is four), but it is the single most compelling argument I can think of. The other is that I have always rated Ed Miliband as a smart, decent, humane, principled and above all courageous politician; that, if for no other reason at all, I would back him because – in contrast to the predecessor who went to bed with the old monster and woke up with an antibiotic-resistant strain of political syphilis – he had the guts to take on Rupert Murdoch.

Only now are the fruits of Miliband’s laceration of News International four years ago fully ripening. On a recent imperial visit, as The Independent revealed, Murdoch expressed his displeasure about The Sun’s failure to demonise Miliband sufficiently. It was not merely out of vengefulness that he told its editor David Dinsmore – the Ben Bradlee du jour, who merrily published Kate Hopkins’ depiction of desperate migrant refugees as “cockroaches” – to sharpen its attacks on Labour and its leader. Since Miliband means to legislate against the media-market dominance Murdoch enjoys, the future of his company, he said, is at stake. Within two days of the edict, The Sun went into full persecution mode. The Kinnocking has continued ever since.

You have to admire Murdoch’s powers of recovery. He has bounced back wonderfully from the humblest day of his life – the 2011 interrogation over phone hacking. Having shrugged that off as he once did prostate cancer (as if a tumour could survive in that bloodstream), today we find the Australian-born naturalised American citizen brazenly trying to fix a British general election in his own financial interests.

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In that noble ambition, of course, he may not be alone. The tax-exile owners of The Daily Telegraph, though more genuine and unflinching Tories by nature, and less interested in dictating editorial policy, presumably find a happy coincidence between their paper’s political stance, their own beliefs and their prospective bank balances. Possibly motivated in part by a desire to avenge itself on Miliband for daring to counter its crazed depiction of his father as “the man who hated Britain”, the Daily Mail also tends mildly toward the partisan.

These three titles, formidable enough individually, form a fearsome troika when they come together. And come together at election time they usually do, by and large replicating the same attack lines, but sometimes divvying them up them for maximum effect. The day after a conclave of editors in 2010, each of their papers splashed with a different but equally aggressive story about Nick Clegg. The naïve might almost have suspected this was orchestrated by, or at least in league with, Conservative high command.

In pictures: Experts' predictions for the General Election - 19/04/15 Show all 10 1 /10 In pictures: Experts' predictions for the General Election - 19/04/15 In pictures: Experts' predictions for the General Election - 19/04/15 Andrew Hawkins (ComRes) “I am thinking Labour will be the largest party. Cameron is making no headway and refusing the debate was a misjudgement. Even if the Conservatives are the largest party I cannot see how they can win enough seats to form a viable alternative to an Ed-led, three-way arrangement with the Lib Dems and SNP.” Andrew Hawkins In pictures: Experts' predictions for the General Election - 19/04/15 Joe Twyman (YouGov) “Ed Miliband’s performance at the challengers’ debate could boost his ratings, and may result in a short-term boost for his party’s fortune, but I think it unlikely to change the overall picture longer term.” In pictures: Experts' predictions for the General Election - 19/04/15 Ben Page (Ipsos MORI) “Labour had the better week, and Ed Miliband is improving his personal ratings from a low base, but neither of the two main parties is getting a majority in these numbers.” In pictures: Experts' predictions for the General Election - 19/04/15 Rick Nye (Populus) “Still no change.” In pictures: Experts' predictions for the General Election - 19/04/15 Nick Moon (GfK) “I agree with Rick [Nye, who said “no change” last week]. Most campaigns don’t really see much change.” In pictures: Experts' predictions for the General Election - 19/04/15 Damian Lyons Lowe (Survation) “On the balance of Thursday’s debate – I’m staying unchanged.” In pictures: Experts' predictions for the General Election - 19/04/15 Michelle Harrison (TNS) “The Conservatives and Labour have barely moved. The most notable event? The SNP hitting 52 per cent on the latest TNS Scotland poll. A key theme for this election is the impact of ‘edge’ politics on the centre.” In pictures: Experts' predictions for the General Election - 19/04/15 James Endersby (Opinium Research) “Our poll gives the Tories a four-point lead. It was carried out either side of Thursday’s TV debate so we haven’t seen the expected dent in Tory fortunes yet. The pattern we’ve seen for a while now appears to be unaffected by week-to-week events. If our figures hold fast, the Lib Dems would still be kingmakers as Tories plus DUP wouldn’t equal 326 seats, but neither would SNP plus Labour. Both sides would need the Lib Dems to eke out a majority.” In pictures: Experts' predictions for the General Election - 19/04/15 Martin Boon (ICM) “We caused something of a kerfuffle this week with a Tory six-pointer. Looking back over the last four campaigns, on each occasion the incumbent government just failed to reach the vote share achieved on our first campaign poll. As I’m reaching for an answer, on that basis alone I’ll go for 36 per cent for the Tories and 34 per cent for Labour.” In pictures: Experts' predictions for the General Election - 19/04/15 Lord Ashcroft (Lord Ashcroft Polls) He refuses to make predictions. “My polls are snapshots, not predictions.” Rex

Presently, they are engaged in a synchronised campaign to stoke hysteria by screechingly parroting the Tory line about the House of MacBondage in which poor little England will find herself enslaved should the SNP permit Miliband to form a minority government. Why one centre-left party holding power with the tacit support of another with which it more or less agrees on every major issue other than Trident represents a mortal threat to stable governance is a mystery.

Also unclear is whether this putrid Scotophobia, which must obliterate any slim chance the Union had of surviving, will have much traction with the kind of voters who are influenced more by mood than by logic. While there is nothing new in harmonised scaremongering, there may be something novel about its impact. In olden days with an election that revolved around a percentage point or two, the combined stigmatising power of the reactionary Tory press would have been decisive. If it fails to swing it for the Conservatives now, it will be time to start work on that long-awaited requiem to the dominion of the media plutocrats over British politics.

If so, it would be a significant victory for the degraded concept known as democracy, though not the end of the war. These newspapers would remain in battle mode, ridiculing the legitimacy of a minority Labour administration, and staying on auto-pilot savaging mode in the quest for a quick second election with a more agreeable outcome. But it would surely be the beginning of the end, marking the moment the rise of social media and growth in cynicism about the motivation of old media prevented the subverting democracy into a form of corpocracy.

Thus far, the polls have shown little sign that the onslaught is shifting public opinion. Whether another fortnight of Cruella d’Sturgeon headlines will move enough votes in enough marginals to keep David Cameron in power remains anyone’s guess.

But with Ed Miliband now the narrow favourite to be the next prime minister whenever the post-election fog lifts, the electoral mathematics suggest that Rupert Murdoch and his bully-boy brethren are the Tories’ best and last hope. If my dad asked for one additional reason to vote Labour on 7 May, that would be it.

The Independent has got together with May2015.com to produce a poll of polls that produces the most up-to-date data in as close to real time as is possible.

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