The Sun matters less than it thinks it does.
In 1992, a mythology was born because the sheer wrongness of the opinion polls made it look as though there’d been a big late swing to the Tories. The Sun’s extra-vicious attacks on Neil Kinnock in the last week of the campaign gave the paper a pretext on which to claim credit for this ‘swing’.
Its endorsement of Blair in the final days of the 1997 campaign had as much effect as the Enola Gay going back over Hiroshima the day after the atom bomb and dropping a hand grenade.
What has an effect is not so much the Sun’s endorsement as its general political coverage, month after month, year after year. And for ages this has been pro-Tory and anti-Labour. Formalising this bias is neither a surprise nor all that significant.
OK, so we now know for sure that the paper will put itself almost wholly at the service of Conservative Central Office – but the main effect of its endorsement is on the rest of the media. It’s the story du jour almost everywhere.
8pm update: Overheard in the supermarket, a 7ish-year-old boy and his dad: "Who's Rupert Murdoch?" "Rupert Murdoch is a very rich man from Australia who's decided to get rid of our government."