José Sócrates appears a model of smiling confidence as he addresses crowds of flag-waving supporters at campaign rallies across Portugal, “I never saw a pessimist create a single job,” the country’s Socialist prime minister, tells a cheering crowd.

But polls for Sunday’s general election can give him little cause for optimism. They point unanimously to a Socialist lead over the centre-right opposition Social Democrats (PSD) that is too narrow to offer Mr Sócrates any certainty of re-election, much less a working majority.