Their strategists like to say that as soon as the public believes the Conservatives can win the next election, then they can win the next election. The trouble is, the public don't, and are now likely to stay sceptical. John Major grins gamely on, almost heroic in his personal optimism. But in weeks like these he seems reminiscent of Private Eye's famously disastrous football manager, "The ashen-faced Ron Knee", while Tony Blair whooshes round America, playing Virtual Government.
The Staffordshire by- election doesn't, of itself, prove anything. By-elections are more like opinion polls than like general elections. They confront voters with a different question - not "which government do you choose?" but rather, "how cross are you feeling with the powers that be this morning?"
Kicking governments is thoroughly enjoyable. But a fundamentally different thing from picking them - the Tories won back every seat that they had lost this way between 1987 and 1992. But politics progresses by stories. Before Tamworth, the Tories were preparing a story about their regeneration in 1996 that will now have to be postponed.
They had been desperately hoping for a by-election result good enough to be presented as some kind of turning point. And then this - a slap across the chops, a kick in the bottom, a stinging rebuke.
Tory by-election defeats have become almost routine, but this weekend it feels as if Britain is slowly changing hands. Nor should sensible Tories take any pleasure in the shrinking of the Liberal Democrat vote. That too is a warning. If voters' readiness to switch tactically is passed on from by-elections to general elections, then the Government is looking at a much more serious defeat next year than ministers currently expect.
Next year? Yes - as long as the Ulster Unionists don't lose patience with Major, his administration can still survive into 1997. There will be further bad nights, particularly after the local elections. The story of the past few years has been one of political decay and I therefore predict more unpredictable events - another defection, a damaging resignation, an unexpected parliamentary defeat.
But these have become almost routine: an early election would need the withdrawal of unionist backing on a confidence motion, or the collapse of the Government from within, and neither seems likely.
But the Tories' one-vote majority will further diminish the party's ability to shape events. In most important ways, this has become a government condemned to passivity.
Provocative legislation cannot be passed. The European Inter-Governmental Conference is a long, slow game of blocking and kicking into touch. The great economic recovery has become the Conservatives' Godot.
While in office, ministers are able to do relatively little with their formal power, in opposition Tony Blair manages to seem impressively busy for a man with no money to spend. The other half of this week's story has been his remarkably life-like impersonation of a successful, old-time Conservative prime minister. Once, such people were easy to recognise. We knew them by their friends - the American presidents, the directors of international capital, the media tycoons. We knew them by their calm assumption of the moral leadership of the middle classes. We knew them by the ruthless professionalism of their political organisation. And we knew them above all because they claimed almost to be above politics, standing for the nation against the scheming of political extremists - in the days when to be "political" meant to be left-wing.
Blair claims every description for himself. He is confidential in the White House and worldly in Wall Street. He advocates Labour as good for investment. By background and conviction, he is a middle-class leader of a somewhat traditionalist stamp; his rhetoric on taxes and crime would have been regarded as right-wing during the Heath years.
When it comes to professionalism, Labour is now hard to beat. The Daily Telegraph now uses phrases like "carefully designed" and "meticulously planned" to complain about the smooth, content-free professionalism of new Labour, rather as the left once used to believe that the Conservatives' brilliant organisation was somehow unfair and un-British.
And finally, by ditching the word "left", Blair completes his journey to a politics which claims to be above faction, class or ideology, standing for the whole nation.
Once a left-wing party, then a party of the "Left-and centre-left", then just of the centre-left, it is now apparently to be simply a party of the centre. That is pushing things further than anyone dreamed possible a few years ago.
It is easy to mock. These are things Blair needs to do to end the Tory century. But they affront real Tories and old Socialists alike and because of the despair felt by some Labour MPs about it, Blair's revolution may yet end in tears.
The lesson of the past few days, however, is that any such tears will be shed almost certainly in government, not in opposition.Reuse content