What now for Frank Dobson? As his friends last night blamed Downing Street for the humiliating defeat, the future looked far from certain for the former Secretary of State for Health.
Mr Livingstone, in his victory speech, said Mr Dobson had "borne a terrible brunt of odium", which should have been reserved for people who worked "behind the scenes".
As Mr Livingstone swept off for a walk-about, Mr Dobson left the QE2 Centre in Westminster, where the prolonged count took place, in his black-windowed campaign mini-bus, without saying a word. Later, he had lunch on the terrace of the Commons with his wife and his close campaign team, including Ann Keen, his former ministerial aide, and Clive Efford, the MP for Eltham, south-east London. He then drove to Millbank to thank his campaign team.
Mr Dobson was keeping a brave face in spite of the defeat. He refused to join in the recriminations and turned down the offer of a substantial five figure sum from a Sunday newspaper for the inside story of his campaign disaster, in which he came within a whisker of being forced into fourth place.
But ministerial colleagues and friends of Mr Dobson, who gave up his Cabinet seat as Health Secretary to run for mayor at Tony Blair's bidding, accused No 10 of "shafting Dobbo". "I feel very sorry for Frank," said a minister. "He is a very capable politician, but Downing Street got it hopelessly wrong by interfering, just as they did over Alun Michael in Wales. The voters thought he was Blair's poodle and Frank is certainly not that."
Another friend said: "I think Frank has been incredibly let down by the system. Frank has been the whipping boy for other people's failures. He was shafted."
Mr Blair yesterday telephoned Mr Dobson from Northern Ireland to thank him for running against Ken Livingstone. Mr Blair could give Mr Dobson a peerage but friends said the MP did not want to go to the House of Lords.
Mr Dobson's friends are hoping he will return to the centre of politics at Westminster, but there is not likely to be a place for him in Mr Blair's next Cabinet reshuffle in July. "Blair can't put a failure in the Cabinet," said one of his opponents.
A senior party source said: "I don't think he will be out of public life for very long. He is an amazing character with a lot to offer."
In his speech at the count, Mr Dobson said he accepted his fair share of Labour's failure but said he hoped he had not let too many people down. Although he had lost the election, he had enjoyed the campaign and did not regret his decision to stand.
To loud applause, he said: "I continue to believe that in a democracy we have to tell the people the truth whether it turns out to be popular or not."
Mr Dobson, who was persuaded to run at last year's annual Labour party conference, criticised Downing Street at the start of the campaign for its "stop Ken" campaign, which he believes backfired against him.
The manoeuvring included the electoral college system giving extra weight to the votes of MPs to try to prevent Mr Livingstone from being selected.
Mr Dobson remains convinced he could have defeated Mr Livingstone in a one-member, one-vote ballot for the party's candidate, which would have prevented the former GLC leader being cast as the victim of a No 10 "stitch up".
Some of the Labour campaign team at Millbank were also keen to avoid sharing the blame for the debacle. Mr Dobson was privately accused of running a lacklustre campaign, and of being caught too often on the defensive by Mr Livingstone, particularly over the Government's plans for partial privatisation of the Tube.