Or possibly against the Conservatives. Their Leader, the Prime Minister, pretty much declared for Remain or Bust yesterday, but hardly anyone even noticed. The reaction, if any, has been that, "We knew that already."
The Leave heartlands of Wales and the North have little or no immigration, to match their few or no non-Labour MPs.
If that is a bad thing, then it is the fault of UKIP, more or less for existing at all.
The one man who would be in a position to reframe the debate in terms that were not toxic to most voters would be the triumphant Len McCluskey.