It doesn’t matter how loyal a candidate is. Once elected, all MPs (to a greater or lesser extent) conclude they have won their seat because of their unique qualities and personal vision. When they look in the mirror, many will see a future prime minister. Almost every backbench MP believes they are one reshuffle away from ministerial office.

Managing 450 MPs is a tall order for any party leader. As prime minister, Keir Starmer would have his work cut out managing the payroll vote of 150-160, especially as only around a third of the new parliamentary Labour party will have been in office before. A big Starmer win would inevitably pave the way for new Labour tribes, each with their own instincts, demands and ambitions. Blairites vs Brownites will feel like a thing of the past as new factions form around place, age and identity.

A big Starmer win would inevitably pave the way for new Labour tribes

Historically, Labour’s heartlands dominated its backbenches – blocs from Scotland, Wales, and Yorkshire got together, traded votes and secured positions. Recent polls paint a different picture: Labour’s heartland is predicted to be in the north-west with more than 70 seats – perhaps a tribute to the mayoralties of Steve Rotheram in Liverpool and Andy Burnham in Manchester.

Then there’s that other mayoralty, London, which may end up not far behind with perhaps more than 60 Labour seats. In the south-east more widely, the party is tipped to gain 30 seats – much of the demographic change driven by London house prices pushing Labour voters into commuter towns. Add to this the candidates outside the capital who earned their spurs politically as councillors in London boroughs (and will therefore bring with them a more metropolitan version of progressive politics) and you have a sizeable bloc.

All in all, nearly half of Labour MPs may end up coming from London, the south-east and the north-west. These three groups could find themselves clashing on where investment should go, as well as on the frequent anti-London rhetoric of Burnham and his allies.

Geography will be just one potential flashpoint. The debate on trans rights, the speed of Labour’s move to back a ceasefire in Gaza and even the row about whether to reinstate Diane Abbott have all been thorny issues which have split Labour. And not along traditional left-right lines either: often it’s been along age lines. This will be a very young party (another consequence of the deep defeat in 2019), which will drive the backbench political demands in many ways. Renters’ rights will matter more than the triple lock. Taxation on wealth will be demanded – particularly on domestic property – rather than on work. Issues of equality will be common currency, not something derided as ‘woke’.

Nor has the hard left gone away. There are still 35 members of the Socialist Campaign Group. The selection process means there’s only a handful of new candidates from this bloc, such as Faiza Shaheen, a Corbynista likely to unseat Iain Duncan Smith in Chingford. But the existing ones are changing their tactics too: advocating a red-green politics that has broader support than older hard-left positions and dominating modern communication channels, as Zarah Sultana and Nadia Whittome from the 2019 intake do on TikTok.

Starmer may not be interested in radical change – but he may struggle to drain the energy and idealism of a Labour parliamentary party that will be keen to seize what could be an unrepeatable political opportunity.