With the election for mayor of London on 3 May Boris Johnson, the Conservative Party candidate, is now moving ahead of his traditional rival, Labour Party candidate Ken Livingstone. The race is still too close to call but polls are giving Johnson a few points ahead of Livingstone.

Johnson has been appealing to businesses in London in the last days of the campaign and is also promising to create 200,000 jobs in the next four years if he is re-elected.

The third candidate in the race is the Liberal Democrat, Brian Paddick, whose vote could be decisive in who wins the election.

Under the supplementary voting system in force voters express a first and second choice of candidate. If no first choice candidate wins an outright majority, all but the first two candidates are eliminated. The second choice votes of the eliminated candidates are then distributed to the first two candidates.

The Green Party, the British National Party, the UK Independence Party (or Free Choice for London) and one independent candidate are also contesting the election.

On 3 May voters in London also ballot for 25 members of the London assembly; 14 of these represent each individual London constituency and 11 are voted as London-wide assembly members.