Prime minister David Cameron
Cameron has waved goodbye to old stagersReuters

David Cameron's shock, root-and-branch reshuffle has had the single overriding objective of approaching the 2015 general election with what he hopes voters will see as a new government.

The prime minister is painfully aware that he has not yet done enough to set himself on course for an outright victory next year and that voters may be tempted by a change of personnel at the heart of government.

He is equally concerned allegation that his erstwhile "male, pale and stale" government is vulnerable to attacks it is out of touch with ordinary voters.

So, by swinging the axe as brutally as he has done, he undoubtedly hopes it will look like the change has already happened and the team he will present to the public will look and sound fundamentally different from the one he has just dumped.

The move to promote a swathe of young, able women is something he has been promising from day one in 2010, but has been sensitive to the criticism once levelled at former Labour prime minister Gordon Brown that his women ministers were "window dressing", as claimed by Caroline Flint.

Most on the Tory benches welcome the promotions, although there have been whispers that Cameron is taking a huge risk in promoting people so quickly, just a year ahead of a general election.

And there is no doubt that the new ministers will have to prove their worth pretty speedily and avoid some of the bear traps that can open up in front of untested newcomers.

William Hague
Hague will leave parliament next yearReuters

But individuals like Anna Soubrey, Nicky Morgan and Clare Perry have already shown they have the abilities to take on significant roles.

Meanwhile, Cameron has also attempted to beef up his election machine by moving both William Hague and Michael Gove into key presentational jobs.

Hague had already told Cameron he was going to step down as an MP in 2015 and the prime minister has decided to use his formidable talents by getting him to tour the country spearheading the grassroots election campaign along with being leader in the Commons and Cameron's party deputy.

Gove has taken a pay cut and demotion from full cabinet, although he will still attend meetings as chief whip. He is also significantly charged with being the government's "minister for the Today programme" with the power to roam across all ministries when it comes to presentation.

And it has been confimred that he had been in talks with the prime minister about such a move for a couple of weeks.

Finally there is the changing political face of the government with the departure of Euro enthusiast Ken Clarke and promotion of right-wing Eurosceptic Philip Hammond.

The balance between the two factions, and the right and left of the party may not appear significantly different one way or another. But it is quality not quantity that counts here.

And the fact that Hammond has previously said he would be ready to take Britain out of the EU if the government could not negotiate significant change in the relationship marks a clear hardening of the line over his predecessor.

Similarly, by replacing attorney general Dominic Grieve with Jeremy Wright, the door appears open to Cameron making a manifesto commitment to withdrawal from the European Court of Human Rights.

There are, inevitably, some real downsides to such a massive and unexpected reshuffle.

Labour has already branded it the "massacre of the moderates" and there will be some rumblings from those moderates and the "old lags" who may feel they have been sacrificed for largely presentational reasons.

Similarly the pro-Europeans in the party will see the moves as yet more concessions to the sceptics and, perhaps another step towards taking the UK out of the EU.

So, as with any major reshuffle, there will be a band of potentially disruptive backbenchers and former ministers nursing resentments and bruised egos.

The prime minister must be banking on the fact that, with less than a year to go to the general election, those dissidents will look to their own constituency seats and behave themselves.

And he will be keeping his fingers crossed that the all-new, Mumsnet-friendly, youthful team – all in relative terms of course – will be the fundamental image change needed to convince voters the Tories are genuinely in touch with their concerns.