Martin Baxter has an article here showing tectonic voter migrations in the lead up to the 2015 U.K. election.
This chart shows just how complex current U.K. politics is. It also shows how standard right-left descriptions can be misleading. Ukip (‘right-wing’) draws from Labour (‘left-wing’). Green (‘left-wing’) draws from the Conservatives (‘right-wing’). Conservatives (‘right-wing’) draw from the Lib Dems (‘left-wing’).
You can get insight into the U.K. election with our election sim here.