Labour's dominance of the left wing has slipped in the last two years

Parties' share of Britain-wide centre-left and leftwing collective support in monthly voting intention polls

(Please use a modern browser to see the interactive version of this visualization)

Guardian graphicSource: PollBaseNotes: Figures are for the share of the monthly average of Labour, Lib Dems, Greens and the Independent Group's collective vote share. Progressive parties SNP and Plaid Cymru not included as not Britain-wide. Runs to December 2025.