Keir Starmer’s starting position as Labour leader is not hopeless, as many think. There is a viable strategy for him to win the next election. But he doesn’t yet have a strong enough appeal to the critical voting segment he needs to win over, and unless he can establish a strong leadership rating among them within the next few months, he will be doomed.

Labour is 124 seats short of a majority, so the voters it needs to win are those that live in the 124 seats Labour is closest to winning in. Within these, the key target voters are those who were open to voting Labour in 2019, but ultimately did not [1].

This group decides whether parties gain majorities. In 2019, the Conservatives gained 44% of voters in their 100 most marginal seats who were open to voting Conservative in 2017 but did not, enough to close a 10–15% gap in these seats. In contrast, Labour gained just 12% of equivalent “Labour considerers” in their 100 most marginal seats.

If Labour wins the 2019 version of this “target Labour considerers” group it will almost certainly be in government. They account for about a fifth of voters in these target seats, while Labour is 20.8% behind in Croydon South, the last seat it needs to win for a majority. Swinging a voter from the winning party reduces their vote share as well raising Labour’s, so swinging most of this group would be enough to win every one of these target seats.

But these voters are harsh judges. Close to three-quarters of target Labour considerers voted Labour at least once since 2005, and over half did so in 2015 or 2017 alone. But in 2019, 51% voted Conservative, 19% Lib Dem, 11% SNP, 7% Green. Labour cannot sit still if it wants to win.

It also cannot win a majority by winning one extra demographic slice.

Target Labour considerers have no single dominant demographic and look like Britain as a whole. Their age, education, gender, ethnicity, and tenure mirror the population, and they voted 55% leave, 45% remain. Slightly more of this group identify as working class than the population overall at 47% compared to 38%, but this is still less than the number identifying as middle class or no class at all, as in Britain overall.

The lesson is simple. Narrow appeals to specific social groups like the working class, non-degree holders, or town-dwellers will fail. To win, Labour must gain support across demographic divisions.

The key to doing this is competent leadership.

Perceptions of Jeremy Corbyn were critical in pushing target Labour considerers to ultimately not vote Labour. There was nearly a perfect relationship between liking Corbyn and voting Labour among those who were open to voting Labour in its 124 target seats. Leadership variables dominate every other factor, including Brexit.

If Keir Starmer cannot convince these key voters that he is the best choice for Prime Minister, he will never get close to Downing Street.

His ratings so far are not enough[2]. Target Labour considerers rate him exactly neutral on a like/dislike scale, an improvement on Corbyn in 2019, but no new dawn. Indeed, this rating is almost identical to Corbyn’s rating among this group in 2017, putting Labour nowhere near a majority.

Starmer’s first steps will be crucial. 57% of target Labour considerers are yet to make up their mind about him. Ipsos MORI’s polling archive of oppositions leaders since Michael Foot suggests that first impressions are crucial. Every opposition leader who failed to become Prime Minister had a negative rating after their first year. In contrast, Tony Blair was at +27 with 51% approval 24% disapproval and became the only opposition leader to win a majority. Cameron was second best after his first year with a negative rating of -5, but received a second wind after 2008 that pushed him into the positives before 2010.

The bottom line is that Starmer cannot afford to fall flat with the public in the months ahead.

One weakness Starmer has is that his support is lower among voters who hold more culturally conservative views. But that does not mean that the right strategy is to toughen Labour’s stance on social issues.

When voters are placed on a liberal-authoritarian scale, target Labour considerers are on average slightly culturally conservative, while Labour is rated as slightly liberal[3].

But when we control for leadership ratings and policy competence, culturally conservative Labour considerers in target seats are not more likely to have voted Labour than those with liberal views, while perceptions of policy competence still make a significant difference.

This makes sense because most swing voters do not have a consistent cultural ideology. Just 22% of target Labour considerers are consistently liberal or conservative on the 5 social issues asked by the British Election Study.

It is policy competence not policy position that matters most to them.

This is even the case on Brexit. The key dividing line between Labour considerers in target seats who voted Labour and those that did not was not between Leave and Remain, but between those who thought a potential Labour government would handle Brexit well or badly. 77% of those who did not vote Labour said it would handle Brexit badly and just 8% said it would handle Brexit well, compared to 34% of those who did vote Labour saying it would handle Brexit well and 36% badly.

A better approach would be to move the political fight back onto economic issues and de-emphasise the culture war. This would be effective since target Labour considerers are significantly closer to Labour than the Conservatives on the left-right economic spectrum.

This is likely to happen no matter what Labour does due to the enormous disruption caused by coronavirus.

But Labour has a severe weakness on economic policy that Starmer must address.

Target Labour considerers simply do not trust Labour with the public purse. 58% said that they thought that if there was a Labour government the economy would get worse, and only 15% said it would get better. Economic credibility is roughly two-thirds as important as leadership ratings in explaining why these swing voters did not vote Labour in 2019, even when Brexit dominated.

The source of this problem is once again competence. According to Sir John Curtice’s analysis of Labour’s economic policies, “where Labour struggled was in persuading voters that the party had the ability to deliver, including in respect of policies that were widely popular. It is also on perceptions of competence — and not for the most part the party’s policy positions on business and industry — that the party was most likely to be found wanting by voters in those groups in which the party performed especially badly.”

So how does Starmer convince target voters that he is a credible Prime Minister and that Labour can deliver on its promises in the midst of an all-consuming crisis?

One Labour leader did it before. After a decade of Labour wilderness, in 1945 it was Clement Attlee not Winston Churchill who the public chose to lead the nation’s reconstruction. The reasons why are instructive: Mass Observation’s 1945 polling report notes that the key words voters used when picking their preferred Prime Minister were “Sensible”, “Straightforward”, “Reasonable”, “Constructive”, and “Grown-up”. It concludes that “After six years of emotion, of glory, of tragedy, of heights and depths of feeling, one gets the impression that people were weary of being roused by any kind of political emotion… Thundering oratory and brilliant repartee were alike out of place; the audience wanted simple common sense and nothing else.”

If Starmer follows Attlee and becomes the no-nonsense, competent, constructive leader, he may well be the next Labour Prime Minister.

[1] The British Election Study asked respondents how likely they were to vote Labour from 0 to 11, so a reasonable measure of a voter open to voting Labour is everyone who responded 4 or above. This turns out to be roughly 55% of the electorate, which seems like a reasonable upper ceiling since it matches Labour’s highest ever polling ratings in the late 1990s.

[2] Note that this is data from the BES Wave 19 that was collected at the end of Dec 2019, but Starmer’s ratings in Ipsos MORI’s polling of Labour leadership candidates have remained fairly constant since so these figures are unlikely to have changed a great deal since this fieldwork.

[3] Labour’s position is taken from the average position of experts in the British Election Study Expert Survey. This average expert rating very closely matches voters’ rating of Labour on a 10 point left-right scale so this appears to be a valid measure of how voters themselves see the parties.