Who will tell her it’s over? Which member of Hillary Clinton’s inner circle will have the courage, the self-abandonment, the capacity for suicidal valour in a greater cause, to walk into that propeller?

After the Democratic primaries on Tuesday in North Carolina and Indiana, someone will have to do it unless the candidate saves them the horror by accepting defeat herself.

Mrs Clinton can go on. She has every right. Barack Obama has still not formally clinched the number of delegates necessary to win the nomination. There are still six primaries in the next four weeks, together with a struggle for the votes of the party’s uncommitted super-delegates, and perhaps one final battle over Florida and Michigan, whose primaries she won but whose delegates are not supposed to count because the states broke party rules.

Yes, she still has an arithmetical chance. But only as a football team has a chance to avoid relegation if it wins all of its last seven games by three goals or more, and then manages to persuade the Premier League to change its rules about who goes up and who goes down.

Make no mistake. Whatever charade unfolds in the ebbing weeks of this campaign, it’s over. Hillary’s bid for the presidency, in the words of Monty Python, has joined the bleedin’ choir invisible.

The recriminations will soon begin. How was it that a candidate dubbed inevitable six months ago could be rolled over by a man who was not even in the Senate when she was putting her presidential campaign team in place?

There are some tentative answers. She ran on a message of experience and a tableau of fond recollections of a recent Democratic past when the party’s voters were desperate for novelty and change. To this strategic blunder she added catastrophic tactical mistakes.

She had no plan in place for the crucial phase of the primaries that followed Super Tuesday, the period in which Mr Obama’s cannier planning laid the groundwork for eleven straight victories.

She stuck by senior advisers who refused to change course when the going got rough. She let her husband off the leash — a freedom that has caused her so much pain in the past and which has now inflicted intolerable political hurt.

This discussion lies in the future. The former First Lady is a tough, resilient politician. For now her task is to figure out what to do next. This will surely not be the end of her presidential ambitions. The question is what is the best way now to pursue them?

As the primary campaign winds down, should she actively seek to be Mr Obama’s vice-presidential nominee?

All the indications from the Obama camp are that he seriously does not want her on the ticket. But he may feel considerable pressure from the grandees of the Democratic party to make a gesture of reconciliation and sign her up.

Then again, does she actually want the job? If she becomes his No 2, and he wins in November, she will be a mere supporting figure in the Obama iconography for the next four years — eight if he wins re-election. If he is going to lose to John McCain, she might be better off not being on the ticket at all, but waiting loyally in the wings, ready to pick up the baton again in 2012, armed with the most powerful “I told you so” argument in the history of politics.

For a while longer, the Clinton campaign will keep up the pretence that she is still in the race. But what matters now, at least for her, is how — she gets out of it.

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