Labour loses Caerphilly Senedd by-election to Plaid Cymru

Labour has lost the Caerphilly by-election, ending more than a century of near-unbroken dominance in the South Wales Valleys.

Labour’s candidate Richard Tunnicliffe placing third and securing just 11% of the vote, with 3,713 votes – down from 46% at the 2021 Senedd election.

In a close contest, Plaid Cymru’s Lindsay Whittle won the seat with 47% and 15,961 votes, with Reform’s Llyr Powell placing second on 36% and 12,113 votes.

Turnout at the by-election was 50.4%, the highest turnout figure for a Senedd by-election and up from 44.3% in 2021.

Labour had held Caerphilly either at Westminster or at the Senedd at every election since 1918.

Labour sources after the polls closed admitted that the party had lost the constituency, with one Welsh Labour source telling LabourList that the picture on the ground was “looking bleak” and said “grim faces” had come back to the party’s office in Caerphilly.

Welsh Deputy First Minister Huw Irranca-Davies told BBC Wales that Labour voters on the doorstep had said they were lending their vote to Plaid to prevent Reform from being elected.

One Labour source also told the BBC that the defeat in Caerphilly was a “defeat for Starmerism, not for First Minister Eluned Morgan”, but warned that Morgan needed to “assert herself” and do more to differentiate Welsh Labour from the UK-wide party before the Senedd election in May.

The seat became vacant when sitting Welsh Labour MS Hefin David died unexpectedly in August, triggering the by-election. Labour had held Caerphilly ever since the Senedd’s inception in 1999, and consistently in Westminster.

A Welsh Labour spokesperson said: “Welsh Labour would like to thank everyone who came out to support our campaign and vote for Richard Tunnicliffe.

“Hefin David loved this constituency and its people. He’s been at the heart of our campaign throughout. This has been a tough campaign for the party for a variety of reasons, but we’re proud of what our staff and volunteers have achieved over the past six weeks and are committed to continuing to fight for Caerphilly and the Valleys.”

Polling of the constituency by Survation in the week prior to the election suggested Labour was trailing in a distant third with just 12%, behind Reform on 42% and Plaid Cymru on 38%.

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It comes as Welsh Labour faces disappointing polling ahead of next May’s Senedd election, which will be the first to be fought on a fully proportional system.

The by-election loss has an immediate effect on the Welsh Government, leaving Labour two seats short of a majority in the Senedd. The result means Labour will need the support of either Plaid Cymru or the Conservatives to pass the budget next year.

Caerphilly will likely be the last by-election for the Senedd for the foreseeable future due to the change in the electoral system from next May.

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