The lesson of yesterday's elections. Unlike his predecessors, Cameron is under siege from two sides
By Paul Goodman
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Conventional wisdom is that elections are won from the centre. That image naturally leads to debate about where "the centre ground might be", and whether the image works in the first place: are elections really won in a centre ground or in a common ground?
Centre-right commentators such as Matthew D'Ancona have argued that in the wake of the American Presidential election result that the conventional wisdom holds true - and, deceptive though transatlantic parallels can be, making the comparison is alluring.
In both countries, ethnic minority voters vote left and are growing fast. In both, women tend to lean left and men right. In both, perhaps above all, the appetite for state dependency is more resilient than it was during the 1980s.
And in both, too, the leadership of centre-right parties lacks natural affinity with blue collar voters. What David Frum has called "the right-wing entertainment industry" claims to speak for these swing voters, but is more truly the voice of parts of its own core constituency.
But none of these post-war leaders had to live in the world of 2012, rather than that of Margaret Thatcher's 1979 or Harold Macmillan's 1959. None of them had to appeal to an anti-politics electorate.
It goes almost without saying that, however well UKIP does in Corby and elsewhere today, turnout will be higher at the next general election, and it is most unlikely to win any Westminster seats. But it won't need to do so to put Ed Miliband in Downing Street.
All it has to do is to take votes from Mr Cameron. And this it will do, regardless of what the Conservative Party does about the EU - because UKIP's voters are angry, marginalised, anti-political class voters.
The right EU policy - taking the road towards withdrawal and a referendum - would help greatly. But though it is necessary, it is not sufficient. Unlike Thatcher, MacMillan, Churchill, Disraeli - any of his predecessors - Mr Cameron is under siege from both left and right.
No wonder Labour, originally the party of the working man, finds itself wondrously transformed into the new ruling class. Buttressed by vote distribution and outdated boundaries, and boosted by the Liberal Democrat alliance with Mr Cameron, Mr Miliband leads Britain's new establishment.