In theory, at least, this means that these two parties, separately or in combination, deprived David Cameron's Conservatives of their winning majority. Potentially, the Conservative score could have been 347 instead of 306 – a comfortable majority of 22 over the baseline 325.
That said, it cannot be assumed that everyone who voted for the two minority parties would have voted Conservative had there been – as Booker puts it in his column today - a more robustly Conservative alternative, along the lines of the Thatcher offer in 1979, or had a referendum on the Lisbon Treaty been on offer.
However, in some seats the margin between victory and defeat was so narrow that what I call the "UKIP effect" can be more or less assured. For instance, in Bolton West, the Labour majority was 92 and the UKIP vote was 1,901. Dorset Mid & Poole North, the majority was 269 and the UKIP vote 2,109. In Hampstead & Kilburn, the majority was 42. UKIP scored 408 and BNP 328 votes.
Quite what the extent of the effect might have been though, will remain controversial, and it is a question the media and the politicians are reluctant to answer. But one thing is for sure – against one of the most unpopular governments in living memory, Cameron has managed to drag defeat from the jaws of victory.
To future generations, Booker writes, it may seem that the most remarkable feature of the 2010 election was that, after 13 years of one of the most disastrous governments in history, as Britain faces its worst economic crisis for decades, the Tory party failed to win a clear victory. He adds:
From the moment Mr Cameron emerged from nowhere as leader in 2005, his defining characteristic was his ruthless drive to create a new "Not the Conservative Party", in his own image. On issue after issue, from his infatuation with "greenery" and global warming to his insistence that his followers should not “bang on about Europe”, he sought to ditch traditional Conservative values and to pursue the Lib Dem, Guardianista "centre" vote. As for his party's more traditional core supporters, he did not so much take them for granted as treat them with contempt.Booker is then one of the few journalists who takes the "UKIP effect" seriously. Although support for its individual candidates may have looked derisory – with the media and others quick to put down the small parties – UKIP actually polled some 917,832 votes, making it easily the fourth largest party. And, if it has deprived Cameron of 20-plus seats, it has rewritten political history.
Such was the deliberate gamble of Mr Cameron's leadership, and the verdict of last week's election was that the gamble has not come off. For five years, it has been evident to anyone in touch with grassroots opinion that a broad swath of natural Tory supporters – including many readers of this column – have watched the antics of Mr Cameron and his little clique of close allies with bewilderment, frustration and dismay. Rarely can any Tory leader have aroused in many of his potential voters so little positive enthusiasm, even if many did last week reluctantly support his party.
The decision to abandon his core vote and go for the woolly centre, sucking up to the Lib-Dims in the hope that they would gravitate to the Tories, has not paid off.
Even though little Nick Clegg has lost some seats, his party's share of the vote increased by one percent over 2005, delivering him 6,827,938 votes. Taking the near million UKIP votes and the 563,743 polled by BNP, Cameron gambled on ditching 1.5 million to gain a share of the near 7-million Lib-Dim votes. The gamble failed, leaving him with a party virtually indistinguishable from that of the other main parties, and his tenancy of No 10 Downing Street still in doubt.
With the only certainty now that there will be another general election in short order, Cameron needs to walk away from the wreckage of his current strategy or he may yet experience an even bigger failure as the "UKIP effect" takes its toll once again.
On the other hand, last time in 2005, I wrote that it could, "conceivably, deny the Conservatives power at the next election," then adding: "Dispute this if you will. Debate it by all means, but it does not seem to me safe to ignore it." Well, they did ignore it and they are quite capable of doing so again. They really are that stupid.