The Labour party has won over 400 seats (out of 650) in the 2024 UK General Elections, and Keir Starmer is expected to replace Rishi Sunak as Prime Minister. The Conservatives, in power for the last fourteen years, have suffered a rout, losing over two-thirds of their seats. The SNP has collapsed in Scotland, mostly to Labour, and the Liberal Democrats have gained over sixty seats.
To the left of the current Labour leadership, yes.
I think it is safe to say he is just left wing. Corbyn also self identifies as a socialist.
Labour hasn’t been left wing atleast since I started living.