Local London elections caused quite a stir last week as Conservative Boris Johnson ousted left-wing Labour incumbent Ken Livingstone for Mayor of London. Since the creation of the mayoral position in 2000, London has employed instant runoff voting with two-choice ranking (also known as supplementary vote).

In addition to the mayor's race, Londoners also for the third time used proportional representation to elect its 25-seat London Assembly, which employs a mixed member system with 14 members elected by winner-take-all from constituencies and 11 seats added from party lists to make the overall result proportional  to the citywide vote. Instructively, the two largest parties swept all the district seats, but ultimately the council had a fair reflection of party perspective, with six seats added from the party lists to three smaller parties.  Conservatives won eight ward seats to Labour's six ward seats. Conservatives and Liberal Democrats picked up three list seats each followed by the Green party and Labour with two seats apiece. The right-wing British National Party also won its first seat in the London Assembly.

London posts full results and the Make My Vote Count coalition has issued an analysis on how proportional voting affected the elections.