Kim Leadbeater has won the Batley and Spen by-election in a result which will allow Labour leader Sir Keir Starmer to breathe a sigh of relief.Labour faced turmoil if the West Yorkshire seat was lost, but Ms Leadbetter’s success will ease the pressure on Sir Keir.She took the seat with 13,296 votes, a majority of 323 over Tory candidate Ryan Stephenson after a bitter contest.