What does the Birmingham Erdington by-election tell us about Labour’s chances of winning a general election?

Labour have triumphed in the Birmingham Erdington by-election, with former nurse Paulette Hamilton — who was subjected to a series of right-wing attacks on the eve of polling — gaining a 3,266 majority. As the city’s first Black MP, Hamilton has much to be proud of.

For supporters of Keir Starmer, there will be cheer in Labour gaining a higher share of the vote than the nadir of 2019, and unlike two other by-elections in which Labour was defending its seat — the party lost Hartlepool, and nearly lost Batley & Spen — there was a swing away from the Tories.

But while turnout tends to be significantly lower in by-elections than in general elections, the appalling turnout of 27% underlines a massive turnout deficit. You would expect that from Tory voters demoralised by the epic scandals enveloping the government, but Labour threw everything at this seat — including lots of high profile visits from leading figures — and still the overall turnout was lower than the entire vote for the late Jack Dromey, who won this seat in 2019 with just over 50%.

While better than the 2019 low point, Labour won a lower share of the vote — 55.5% — than in 2017, when it chalked up 58%, at the time its highest share since 1997. The Tory vote was also slightly lower than in 2017, but the gap between the two parties in percentage terms is roughly the same. That would suggest a state of the parties akin to 2017, when there was a hung Parliament but the Tories were able to scrape together a minority government with the help of the Democratic Unionist Party.

But what should worry the Labour leadership is: firstly, the Tories are enveloped in one of the greatest political scandals of modern times, with the Prime Minister under police investigation, while there is a cost of living crisis gnawing at the finances of voters who have already suffered the longest squeeze in wages since the early 19th century. There could hardly be more favourable circumstances for a walloping Labour advance — but that has not materialised.

Secondly, opposition parties tend to do significantly better in by-elections than in a general election, because it’s a cost-free opportunity to land a blow on the government. Under Neil Kinnock’s leadership in the early 1990s, for example, you had some absolutely sensational by-election results, not least the Mid-Staffordshire by-election in which Labour’s vote share surged by 24.4%, while the Tories’ vote slumped by 18.3%: it was alas won back by the Tories in 1992 (by Michael Fabricant, no less), with John Major’s party winning the national election.

In that case, precedent generally suggests Labour would do less well here in a general election, which would indicate an overall national result that’s less favourable than 2017. If Labour was to be confident of beating the Tories, it should expect to be securing absolute thumping victories in seats it has won for decades, including at a low-point like 2019. That clearly isn’t happening.

The key problem Labour appears to face — which the testimonies of canvassers points to — is a lack of an enthusiasm for Keir Starmer’s leadership, and for the party as a whole. The question there is: what’s its solution to that, other than aggressively defining itself against its left flank?