Carolyn Harris, the MP for Swansea East, has been elected as the first deputy leader of Welsh Labour, narrowly defeating Julie Morgan, the Assembly member for Cardiff North and former MP for the Westminster constituency of the same name.

Harris narrowly prevailed with 51.5 per cent of the vote against 48.5 per cent of the vote for Morgan under Welsh Labour’s electoral college system – Welsh members of Parliament and of the Assembly represent third of the vote, trade unions and affiliates another third, and party members make up the remaining third – but Morgan, who made changing the Welsh Labour system to the one member one vote (OMOV) system used in Labour leadership contests a centerpiece of her campaign, and was endorsed by Momentum, won among members. However, Harris, who had the backing of every major trade union with the exception of Unison, won among parliamentarians and the trade union section.

That will ensure the issue of how Welsh Labour elects its leader is not definitively put to bed, and it may acquire a fresh edge if, as expected, Carwyn Jones opts to stand down as party leader in the autumn or early in 2019.

However, the simplistic narrative that the contest was a mere referendum on OMOV is not quite the case. Harris’ endorsements included Clive Lewis and Diane Abbott, and as well as Corbyn’s allies in Unite she also had the backing of the pro-Corbyn trade unions of Aslef and the FBU. Equally, Morgan’s supporters spanned the political sphere.

Some in the party felt that the deputy leader ought to be a member of the Westminster parliament, and backed Harris despite supporting OMOV, while some of Morgan’s supporters believed that the deputy leader should be an Assembly member and backed her despite disagreeing on OMOV.

However, that most in Welsh Labour expect a vacancy to emerge at the top in the not-too-distant future means that the question of how the contest should be run will lose none of its edge.