James Frayne is Director of communications agency Public First and author of Meet the People, a guide to moving public opinion. The focus of this column is Theresa May’s conservatism for “ordinary working people”.

Theresa May’s first speech outside Downing Street was perfectly pitched. In shifting Conservative attention to those “just about managing”, she positioned the Conservative Party for the great mass of the public who decide elections: lower middle class, provincial C1/C2 voters. But the compass she set after her arrival was slightly off – and by the time of the election the party had drifted miles away from the destination they hoped to be at.

Instead of ruthlessly focusing policies on these lower middle class families, the Conservatives redefined the just about managing as the working poor. (Whether this was partly down to the civil service is unclear). As such, the Government’s Autumn Statement and the Budget that followed failed to address their concerns in earnest. And when it came, the election campaign failed to speak to them. The Conservatives’ refusal to rule out tax rises was almost perfectly designed to irritate them.

Some within the Party think David Cameron won a majority in 2015 because of his focus on the poorest voters. This is wrong, and it would be a mistake for the party to go back to this orthodoxy that so dominated the party over the last two decades. Cameron finally managed to secure a majority for the Conservatives because he ran a very late campaign for C1/C2 voters against a Labour Party that was hostile to them. Without that late shift, it’s reasonable to assume the party would have been in the position it now finds itself in.

The Conservative Party’s electoral performance depends on three things: securing huge majorities amongst its core AB voters; securing solid majorities amongst C1 voters; and tying with C2 voters. DE voters are useful but they’ve traditionally voted Labour and the Conservatives have never and can never depend on them. This was how the Conservatives won majorities in both 1992 and 2015 – and the slow uptick in their electoral performance from 2005 to 2015 reflected their gradually better performance amongst C1/C2s.

It’s undoubtedly true that the Conservatives have an impending problem with younger voters, which requires urgent attention. The Conservatives need to build a property-owning middle class in the next generation. However, it’s hard not to judge, from the early data that’s been released (by YouGov, Ipsos-Mori and Lord Ashcroft) that the Conservatives lost because they failed to dominate the lower middle class vote. In this election, while they narrowly led with C2 voters, they failed to secure the necessary big win amongst C1 voters – and they also relatively underperformed amongst their core AB voters.

Why didn’t the lower middle class come out for the Conservatives? Well, why should they have? Appealing to the lower middle class depends on two things: generating policies to make their lives easier; and taking positions on cultural issues that speak to their hearts. On the former, the party offered little: they all but pledged to raise taxes; they seemed to threaten a raid on people’s savings for old age; they began to unpick middle class welfare; and they said nothing to address the cost of driving or improving healthcare. On the latter, after an electrifying early conflict with Jean Claude Juncker, they ducked any further substantial conflict with hostile politicians and failed to engage on issues like crime and human rights.

In looking for explanations for electoral underperformance, party strategists should not overlook the obvious: that without locking down the provincial lower middle class it’s extremely difficult to secure a majority. These ordinary “just about managing” families might seem a bit “dull”. They live in commuter towns and suburbs; they drive second hand cars; they work in ordinary jobs; they have mortgages; they hold traditional views on many issues. But they ultimately determine who governs. They must remain the focus of the Conservative Party in the coming Parliament.