Read: What’s the big idea that could win the Conservatives the next election? Social mobility

For political parties, general election victories revolve around extending as far as possible beyond their core vote, into the floating and middle-ground voters. But Boris Johnson’s 2019 landslide was unique in that it was built by fusing together core Conservative and Labour voters for the first time. In 2019, it was the middle ground that had nowhere else to go, scared by the prospect of a Corbyn government.

Yet last week’s local elections showed that coalition under pressure on both sides – “red wall” and “blue wall”. If Keir Starmer’s assertion that his party is on course for No 10 at next year’s general election is correct, it would represent a staggering collapse in support for this Conservative administration. The Blair-led Labour government’s 1997 landslide carried it through three elections. This Conservative administration would have seen its voting base collapse in just one term.

The local election results are a wake-up call. So where does the Conservative party go next?

As prime minister, Rishi Sunak has had some success in steadying the ship after the disastrous mini-budget of his predecessor, Liz Truss. But it’s not going to be enough. Running Britain isn’t the same as leading it. And to lead Britain over the next 12 months, the Conservative party will need to win the battle of ideas and set out a compelling vision of how to deliver them.

With voters now less tribal than they used to be, there’s more switching between parties. Britain is now the national equivalent of a super-complex marginal seat. With no Jeremy Corbyn leading it, the Labour opposition won’t be handing power on a plate to the Conservatives next time voters go to the polls. The party needs to find its own route to victory.

As an MP elected four times in a marginal London constituency, my own experience is that no amount of focus groups or polling is enough to substitute for decent political antennae. Sunak needs to tap into his own instincts to understand the mood of the country and grasp where it wants to go next. He must articulate a sense of hope for change and provide big ideas on how to deliver it. It’s why being in touch matters so much.

Whoever sets out big ideas that resonate with the public will win next year’s general election.

In practice, we already know what the big idea is that wins a landslide: it’s social mobility. The Conservatives are trailing in the polls – particularly in the red wall – because the electorate do not believe the government has made nearly enough progress on levelling up.

Boris Johnson’s government identified the zeitgeist issue – levelling up – that delivered the landslide in 2019. Yet weak social mobility remains this country’s defining issue, a complex social and economic challenge that Johnson himself failed to grasp effectively. Sunak’s government can only stay in power by finally setting out fresh, ambitious and radical ideas on changing the status quo this country has always had – inequality of opportunity.

How we unlock Britain’s talent and connect it to opportunity, irrespective of background, is a social and political challenge; but if we succeed, it will fix Britain’s broken public finances and tackle our growth and productivity crisis. Lives lived off-track and unfulfilled draw far more on public finances than successful lives with access to opportunity. Working out how to make the most of this country’s talent base is the only way to fix a long-term skills problem that is preventing businesses from growing and trapping people in low-paid jobs amid a cost of living crisis.

It’s not all about government – business has a key role to play, too. There are already progressive businesses in Britain that know they have to authentically match the values of younger people if they’re going to attract the widest possible talent as employees – and have them as customers. They’re challenging themselves to operate as engines of social mobility, working as forces for good in their local communities, often alongside local public service providers, further education colleges and universities – the other long-term, anchor institutions at a local level. Companies such as Co-op, with its community fridges and its academy schools, understand that’s how sustainable profits are achieved – by being part of the wider solution that Britain needs to create social mobility. The smartest businesses are already doing this and are sharing their solutions with others.

These coalitions of the willing are good news for a political system that struggles to deliver long-term change. The nascent ideas and action are already out there; Sunak’s government needs to be an enabler for them, rather than a bureaucratic barrier to be overcome. Both the Conservatives and Labour need to be parties of progressive business, aiming for social mobility and social impact. It means creating an environment for that to become the norm. Purpose in business matters. Similarly, transformative politics in the 21st century needs clarity of political purpose, with leadership that can galvanise employers and civil society across the country around solving the common challenge of endemic inequality of opportunity.

Is Sunak up to it? Is Starmer up to it? It’s not yet clear to voters who can deliver the vision and leadership Britain needs for the path that lies ahead. But it is clear that winning over voters will require big ideas for long-term change that go beyond simple political slogans. We literally cannot afford to continue as we are. A message of equality of opportunity was enough to win the last general election for the Conservative party; but it’s only delivering it that will win the next.