A quick, but important, observation which will be relevant for at least one political party after the May general election: the current deadlock between Labour and the Conservatives in the opinion polls is a striking example of how changing leader isn’t enough to make a party into a winner.
Both David Cameron and Ed Miliband, when elected, were meant to be the new leader gloriously leading their party to the 40%+ sunny polling uplands from which they would win a comfortable overall majority. Roll on rule unimpeded by others.
Cameron never finished rebranding the Conservatives to leave their rich, selfish and posh image behind, whilst Ed Miliband (due to his prioritisation of party unity) never even really started on Labour.
Hence the stalemate in the polls – and a lesson too for whichever party next changes its leader.