But Iain Duncan Smith’s sudden and dramatic resignation has crystalised nagging concerns about the chancellor within his own party.
The bookmakers William Hill said it had pushed Osborne’s odds of being the next prime minister from 2/1 favourite to 7/2 second favourite, and shortened Boris Johnson from 3/1 to a 15/8 clear favourite.
William Hill’s spokesman, Graham Sharpe, said: “So sure-footed for so long, Mr Osborne was widely regarded as Cameron’s natural and chosen successor, but recent blunders seem to have dealt him a serious blow to achieving that outcome.”
It is a sentiment now increasingly widely shared in Westminster, where what one backbencher called an “Anyone but George” campaign is gathering force.
The climbdown over disability benefits and the loss of Duncan Smith are the most damaging of a series of recent revolts, including a defeat over Sunday trading laws and the tampon tax rebellion, which forced the prime minister to discuss the issue with his EU counterparts.
Some budget proposals, including a fuel-duty rise and a cut in tax relief on pensions contributions that would have hit higher earners, were ditched even before they went to the printers, as Downing Street sought to avoid any noise in the runup to June’s referendum.
In order to secure the leadership, when the prime minister steps down at some point between now and 2020, Osborne would have to win over enough backbenchers to make it through to the final two candidates, who are then put to grassroots members for a vote.
Osborne had already been eclipsed by Brexiteer Boris Johnson in the hearts of many individual members, who tend to be more Eurosceptic than the Tory party in parliament.
But this latest reversal, which saw the budget unravelling within two days of being delivered – “We’re not wedded to these numbers,” said a Treasury source on Friday of the welfare cuts published in the budget red book – reminded backbenchers that his great strength as a political tactician can also be a weakness.
Osborne, and to some extent Cameron with his pre-election pledges to pensioners and other groups, has trapped himself and his party in a straitjacket of his own making.
His promise to deliver a surplus on the public finances by 2020 was far more about stymying a Labour party struggling with its own attitude to austerity than the national interest. And the welfare cap, similarly, was more a political stunt, aimed at isolating Labour as the friends of scroungers and skivers, than a well thought-out policy.
Yet by tying himself and his party up in all these pledges, promises and targets, the chancellor ended up delivering a budget that – as Duncan Smith pointed out – couldn’t possibly be construed as fair in its own terms.
While the public may approve of the general idea of bringing down the welfare bill, they also understand that politics is about choices, and targeting the disabled while giving extra cash to wealthy shareholders fails the most basic tests of fairness.
Son of a baronet
It also plays to the most damaging caricature of Osborne, as the privileged son of a baronet, keener on protecting his wealthy friends than helping ordinary Britons: something he has fought hard to shrug off by introducing his “national living wage”, for example.
Vince Cable, who served alongside Osborne as business secretary in the Liberal-Conservative coalition of 2010-2015, says the arrogance of the Treasury is one factor that helps to explain the chancellor’s current travails.
Cable says that, time after time as Osborne imposed welfare cuts, Duncan Smith was “dragged kicking and screaming the whole way through: and you had these pubescent Treasury officials saying, a billion from this and a billion from that, without any sense at all of what it meant in human terms”.
Others point out that, while the prime minister has been the public face of the campaign to keep Britain in the EU after June’s referendum, Osborne is heavily involved behind the scenes, distracting his focus from the budget.
That means all Osborne’s tactics have ultimately added up to very bad politics – a lesson that will not be lost on his own backbenchers as they wonder who could best carry them into the next general election.
This article was written by Heather Stewart Political editor, for theguardian.com on Saturday 19th March 2016 12.03 Europe/Londonguardian.co.uk © Guardian News and Media Limited 2010