“Nobody predicted this.” So said a television interviewer to me at about 8.30 this morning. How to rebut that idea before it becomes the received wisdom?

If I’d had my wits about me, I would have said something like: “Tory candidates up and down the country knew this victory was on the cards. Wherever I visited them over the last month for ConHome, they were confident they could cross the finishing line ahead of their opponents. Andrea Jenkyns, Chris Green, Jackie Doyle-Price, David Mundell, Tom Pursglove, Peter Bone and Charlotte Leslie were among those who communicated the belief that they were in with a very good chance.

“They didn’t go round boasting about this – that would have been insufferably complacent, and it would also have been stupid, for the margin of victory was in many cases slim. But they all knew – usually thanks to years of immersion in the issues which mattered most to their voters – that their campaigns were going better than one would suppose from day after day of ‘it’s neck and neck, it’s on a knife edge’ coverage in the national media.”

But perhaps that reply would not have made very good television, and I was in any case incapable, after a sleepless night, of putting it together. So I instead told the interviewer: “As a matter of fact, I predicted it.”

She seemed, rather woundingly, to want proof. Thus it was that I found myself obliged to mention the ConHome Christmas lunch, at which Paul Goodman organised a sweepstake on the simple question of how many seats the Tories would win at the general election. My answer was 330, and my ConHome colleague Mark Wallace said 320.

One can, if one wishes, attribute this to the high quality of the red wine served on this occasion: in vino veritas. But there was actually no need to be even slightly drunk in order to think along these lines.

For at the start of this year it already seemed overwhelmingly probable that the Tory campaign would be far more formidable than the Labour campaign. The Conservatives had serious things to say about the economy, and a convincing record of economic achievement over the last five years: Labour had nothing to say, and a disastrous record over its last years in power. This was a fatal weakness.

Tony Blair and Gordon Brown laid the foundation for the Labour victory in 1997 by putting together a serious economic policy, much of it copied from Margaret Thatcher and her successors. By doing this difficult work, and advertising the fact that they had done it, they reassured people that it was safe to vote Labour. Ed Miliband could not bear to acknowledge a debt to Blair, let alone to Thatcher. When asked about the economy, he retreated into vapid, vaguely leftish verbiage. Voters were not reassured.

The interviewer was of course quite right that none of the opinion polls predicted this victory. But as all the best pollsters know, polls are no substitute for judgment: and even the polls showed that large numbers of people had not made up their minds. How, when at last they thought about the election, would these people reach a decision? This question was ignored.

A few days ago I met a Tory MP on a train. He asked me how I thought the party would do. I replied, cautiously, that I thought it would do better than the polls suggested, and then alluded to my prediction of 330 seats: at which he looked so startled that I did not press the point.

All this has made for a very exciting election night. Expectations were so depressed that they have been exceeded in a most dramatic fashion. David Cameron, George Osborne and Lynton Crosby were underestimated, as were many high-quality Conservative candidates: which makes victory all the sweeter.