When Keir Starmer stepped down as British prime minister this week, it said as much about his troubled premiership as it did about a crisis facing other social-democratic Labour parties.

Much was made of Labour’s “landslide victory” in the UK in 2024, when the party won 411 of 650 seats in the House of Commons. But Britain’s disproportional first-past-the-post electoral system had transformed just one third of the popular vote into a commanding parliamentary majority.

With turnout at only 59.7%, roughly one in five eligible voters actually backed a Labour candidate. In other words, Labour entered office with overwhelming parliamentary power but a shallow democratic mandate.

Since then, the party’s position has deteriorated further, with polling often placing it at 20% or lower as support has fragmented to both left and right.

A 2025 survey of Labour defectors found that concerns about immigration were pushing some voters towards Reform UK and the Conservatives. Others were abandoning the party because it was not seen as progressive enough, driving them towards the Greens and Liberal Democrats.

One factor has united both groups, however: dissatisfaction with Starmer himself.

So, what lessons can New Zealand Labour leader Chris Hipkins draw from these voter trends and his former counterpart’s downfall as he........

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