raises a wider question of such a government's legitimacy. A senior Labour source put it to me this way during the day: "Is a Lab-Lib deal possible on terms that do not court electoral disaster for legitimacy reasons?" It is absolutely the key question. Translated, it means: is it possible for Labour to choose a new leader over the coming months who will be seen as the legitimate leader of a Lab-Lib coalition by the public? Or will another change of leader bring electoral rejection down upon Labour and the Liberal Democrats? The answer to these questions is that no one knows. Brown has given his successor his or her best chance of making a Lab-Lib deal work and making it sellable internally and to the country. It was a brave and dignified statement that must have cost him hours of agonising to make. The game is now afoot. But the Lab-Lib option remains an immensely long odds bet. Don't ring the bells yet. Liberal Democrats will wish that Gordon Brown had agreed to stand down in the hours after the election: by waiting, he delayed the start of serious talks with Labour and drove them into the arms of the Conservatives. Nick Clegg was never likely to agree a deal that kept a defeated prime minister in office. Now he is going, the Lib Dems will be torn. Tempted by a deal with the Conservatives that is close -- but not that close -- to meeting his demands, Clegg