What happens in the run-off between the final Tory candidates?

Politics Explained: It will be a gruelling month for the final two, with CCHQ expected to arrange 16 hustings events in every region and nation of UK

1922 Committee executives read out the results of the first ballot in the Tory leadership ballot at the Houses of Parliament (AFP)

In 2005, a fresh-faced 39-year-old David Cameron emerged victorious as the results of the Conservatives’ leadership contest were read out by the chairman of the 1922 Committee Sir Michael Spicer at the Royal Academy of Arts.

He fended off competition to become the new Tory leader from David Davis by more than two to one – attracting 134,446 votes to 64,398 in a postal vote of party members across the UK.

In the coming month – more than two decades on – some 160,000 members of the party will have another chance to cast a ballot and pass on the Tory crown. This time, however, they will be electing not only the next Conservative leader, but Britain’s next prime minister.