Tom Pridham is a Public Affairs Consultant.

Both Charlotte Gill’s recent piece and Gavin Barwell’s response are clearly right to identify Keir Starmer as a marked improvement on his predecessor.

Recent polling by Ipsos Mori indicates that Starmer – with a net satisfaction score of +31 – is the most popular Leader of the Opposition since Tony Blair. Gill calls into question Starmer’s ability to retain popularity in the long run, due in particular to his advocacy of a second referendum and a desire among voters for clear messages over “forensic brilliance”.

Whilst acknowledging the narrow path to a Labour majority, Barwell implores Conservatives not to underestimate Starmer, pointing rightly to the repelling effect of Corbyn no longer being a factor and the possibility of Labour opening up a new path to victory through London and the South, making it less reliant on the ‘Red Wall’.

However, he also argues that – in the event of a hung parliament – the minority parties would be more amenable to supporting Labour. Whilst undoubtedly true, it is this very fact, and the double lock shutting out Labour that it creates, which makes a Starmer-led government much less likely.

Although Labour’s loss of the ‘Red Wall’ was devastating for the party, its decline in Scotland has been more damaging. Not only has it lost dozens of safe seats that previously formed the core of the parliamentary party, it is now structurally reliant on the SNP to stand a chance of entering government.

Labour would need to gain 123 seats to reach 325 at the next election. Number 123 on Labour’s target list is South Ribble, currently held by the Conservative Katherine Fletcher with a majority of 11,199 – this would require a swing of roughly 10.5 per cent. The scale of this task means that Labour’s only realistic route to government is in a minority, relying on the SNP for support.

This prospect has proved unpopular with voters in England. In 2015, the Conservative Party used the prospect of a Labour-SNP coalition very effectively, with this dynamic one of the key factors in David Cameron’s surprise victory. In 2017, the possibility of a hung parliament was not seen as realistic and – with a large Tory majority seen as inevitable – many voters felt like they had a ‘free hit’. In 2019, the Conservatives benefited from the fact that Labour only needed to gain a handful of seats to enter government, enhancing the threat not only from Corbyn himself but a minority Labour government, reliant on the SNP.

One other possibility would be for Labour to bank on a resurgence of the Liberal Democrats, a much less threatening prospect than the SNP. Whilst fanciful in the current environment, it is far from impossible and the party has shown an ability to rebuild before.

However, this presents the possibility of Labour and the Liberal Democrats coming into direct competition for the same group of voters, blunting the other’s ability to take seats from the Conservatives. Despite suffering four election defeats in a row, Labour has made gains in urban, culturally liberal areas that voted strongly to remain. This has now begun to spill out to areas such as Canterbury, which has seen an influx of voters escaping the high living costs of London. This trend could extend to other parts of the South East, particularly if the COVID-19 pandemic makes home-working more commonplace and decreases the need for middle class professionals to commute to the office.

However, these seats are exactly the kind of seats that the Liberal Democrats will also be targeting – affluent, middle class, remain-voting and socially liberal. This makes it incredibly difficult for Labour and the Liberal Democrats to get to a position where they could govern together without relying on the SNP.

This presents a difficult situation for Labour in an election campaign. If Starmer is perceived as performing well (which appears very possible) and the polls narrow, then Labour will be seen as having a realistic prospect of entering government.

However the distribution of party support means that Labour surging to a majority in one electoral cycle is simply not a realistic prospect. If Starmer does improve Labour’s polling position going into the next election, he therefore increases the potency of the Conservative argument about the danger of the SNP. It is this structural reality – and its strength as a campaigning message – that is likely to do much more harm to Starmer’s chances of becoming Prime Minister than any personal failing on his part.