Sir Keir Starmer’s Labour Party has lost the by-election in Caerphilly. In a historic political upset, Plaid Cymru snatched the Caerphilly Senedd seat for the first time since it was created in 1999. Labour had held the parliamentary seat for over a century. Lindsay Whittle’s Welsh nationalist party candidate was moved to tears when he heard he had secured 15,960 votes and a historic victory. Mr Whittle, 72, has stood as Plaid candidate 13 times since 1983, and will now hold the seat until the Senedd elections next year.

In a further blow for Labour, Mr Starmer’s party was left trailing in third place behind Plaid and Reform UK after Nigel Farage pledged to “throw everything” at the campaign in the hopes of winning his party’s first seat at the ballot box. Plaid emerged with a majority of 3,848 votes and a swing of almost 27% from Labour on a high turnout of more than 50%. Reform candidate Llyr Powell got 12,113 votes – a sharp rise from the 495 the party got four years ago – and Labour’s Richard Tunnicliffe trailed behind on 13,289, down from 2021, when there was a lower turnout.

As well as posing a setback for Labour, the result is likely to embolden the nationalist party in its efforts to enter government in Wales next year.

Mr Whittle said: “I’ve spent my whole life fighting for this community, and I won’t stop now. Tonight’s result shows what’s possible when people come together to back practical solutions and protect what matters most.

“We’ve beaten billionaire-backed Reform and, with the same determination, we can do it again in 2026. Caerphilly has shown the way – now Wales must follow.”

“I hope that this will now be an exciting time for politics in Wales,” he added. “I’ve been absolutely heartened by the number of young people who’ve been involved in this campaign.”

The 72-year-old also directly addressed the UK government, warning that the vote showed that the Welsh people “want a better deal”.

“We are at the dawn of a new leadership, we are at the dawn of a new beginning and I look forward to playing my part for a new Wales, and in particular for the people of the Caerphilly constituency,” he added.

While Labour has led the Welsh Parliament since the devolved administration was first established 26 years ago, Plaid Cymru and Reform UK are forecast to become the two biggest parties in Wales next year.

First Minister Eluned Morgan said: “This was a by-election in the toughest of circumstances, and in the midst of difficult headwinds nationally. Welsh Labour has heard the frustration on doorsteps in Caerphilly that the need to feel change in people’s lives has not been quick enough.

“We take our share of the responsibility for this result. We are listening, we are learning the lessons, and we will be come back stronger.”