Seemingly oblivious to reality, Keir Starmer has said he will fight against Andy Burnham in a leadership challenge. We say ‘oblivious’, because Starmer is one of the most unpopular PMs in history, and Burnham just smashed Reform in a by-election despite Farage’s party leading the polls for over a year. Should Starmer defend himself, we now know roughly what he has planned: NEW: A leaked No 10 document shows how Keir Starmer plans to stop Andy Burnham becoming PM “Andy Burnham hasn’t faced any real scrutiny yet. A true contest would likely see his support wane” [@Guardian] pic.twitter.com/Oq5TmYZp1E — Politics UK…