Historic Collapse for Welsh Labour as Plaid Cymru and Reform UK Battle for Control

Labour falls to 13% as Plaid Cymru and Reform UK lead the 2026 Senedd election polls. Explore the historic shift in Welsh politics and the new voting system.

By: AXL Media

Published: Apr 8, 2026, 7:46 AM EDT

Source: Information for this report was sourced from Sky News

The End of a Century-Long Political Era

For more than one hundred years, the Labour Party has been the undisputed force in Welsh politics, winning every major election in the country since the early 20th century. However, as the 2026 Senedd elections approach, that era appears to be reaching a definitive conclusion. According to a March 2026 YouGov MRP poll for ITV Cymru Wales, Labour has plummeted to just 13% of the vote, a catastrophic 23-point drop from previous levels. This collapse has relegated the party to a battle for third place against the Green Party, a development that political analysts have described as a "tectonic shift" in the British political landscape.

A Redesigned Parliament and Voting System

The upcoming election will be the first conducted under a radically overhauled electoral framework designed to modernize the Welsh legislature. The Senedd is expanding from 60 to 96 Members (MSs) to accommodate its increased law-making and tax-raising responsibilities. Voters will no longer cast two ballots for individual candidates and regions; instead, a new "closed-list" proportional system has been implemented across 16 six-member constituencies. This change, utilizing the D'Hondt method of seat allocation, has significantly lowered the threshold for smaller parties to gain representation, contributing to the fragmentation of the traditional two-party system.

Plaid Cymru Positioned for Historic Leadership

Plaid Cymru leader Rhun ap Iorwerth is currently the favorite to become the first non-Labour First Minister in the history of Welsh devolution. Polling projections suggest the nationalist party could secure 43 seats, leaving them just six short of an overall majority in the 96-seat chamber. In preparation for power, ap Iorwerth has published a "roadmap" for his first 100 days in government, focusing on health reform and cost-of-living measures. While he has expressed a preference for leading a minority administration, sources indicate the party has actively studied the Scottish National Party’s 2007 transition to power for guidance on minority rule.