People wonder why Ken rejoined Labour . It couldn't have realy done him much good to get an endorsement from Brown ,but whatever else you say about Livingstone he's always been a smart operator . Possible scenario:
Gordon Brown's popularity continues to plummet . Boris makes a mess out of the mayorship and everybody starts to look back to the halcyon days of the Livingstone era .
Livingstone wins a bye election and becomes the new MP for Brent .
Brown resigns leadership of Labour Party after losing general election to Cameron. Enter the new leader of Her Majesty's Opposition .