“I voted for Ahmadinejad in 2005, but I’ve switched to Mousavi this time because I think he’ll improve the economy. Under President Ahmadinejad inflation has shot up,” Aboldazl Zamani, 45, a bazaari (shopkeeper), said as he voted last Friday at a mosque in Shoosh, a poor area of south Tehran that is an Ahmadinejad stronghold. “My family and relatives have also switched to Mousavi,” he added.

A few votes switched to Mir Hossein Mousavi, the moderate presidential contender, are neither here nor there, of course, but the point is this: in eight hours spent touring polling stations in and around Tehran The Times found a number of Iranians who had deserted Mr Ahmadinejad since 2005, but not one who had switched to him.

Had the election committee announced that Mr Ahmadinejad had won with, say, 51 per cent of the vote, few independent observers could have said with certainty that the election was rigged — Mr Ahmadinejad undoubtedly has millions of devoted followers. But the idea that he won with 63 per cent ran contrary to every manifestation of the public mood before polling day, defied electoral logic, and was simply incredible.

There were those huge Mousavi rallies, and all-night street parties pulsating with the passion and excitement of people who knew the tide was flowing strongly their way. By contrast, Mr Ahmadinejad’s rallies felt more scripted, less spontaneous, with supporters bussed in.

There was the massive turnout of 85 per cent on election day. Low votes favour hardliners such as Mr Ahmadinejad, while high turnouts favour reformers. There is the dire state of Iran’s economy, with rampant unemployment and 25 per cent inflation — unlikely conditions for an incumbent to win by a landslide.

The dirty tricks in the campaign, such as the sudden power cuts that sabotaged opposition rallies, lent credence to allegations of dirty tricks on polling day — shortages of ballot papers in Mousavi strongholds, the declaration of some results before ballot boxes had even been opened.

Of the last dozen (admittedly unreliable) opinion polls, seven put Mr Mousavi ahead. On election eve Mousavi aides confidently told The Times that their man would win between 55 and 60 per cent. The declared results improbably suggest Mr Ahmadinejad won more than half the vote in Tehran, a Mousavi stronghold, and 57 per cent in Tabriz, capital of Mr Mousavi’s native Azerbaijan region.

Mr Ahmadinejad had men in key positions to rig the vote and enforce the result. Sadeq Mahsouli, the Interior Minister, and Kamran Daneshjoo, the election commission chief, are his cronies and appointees.

Perhaps the most damning evidence that the vote was rigged was the sheer speed, scale and efficiency of the subsequent crackdown. The results had scarcely been declared before security forces flooded on to the streets, websites were blocked and mobile telephone and text-messaging services taken down to prevent the opposition mobilising. It had to have been planned in advance.

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