It's a strange experience to celebrate one's failure. But having predicted for years that Hillary Clinton would grab the Democratic nomination - and, I might add, go on to lose - this year's United States election, I found myself giddily welcoming the news that Barack Obama actually pulled it off on Tuesday night.

I overestimated both the hold the Clintons had on the Democratic Party, and their savvy. Mrs Clinton's team ran a weak campaign. She was outsmarted by her more junior peer, whom she dismissed for inexperience. Obama had the sense to put his energy into the caucus states, whereas Mrs Clinton mistakenly thought she'd tie it up with a few big victories. So much for the better judgement born of experience.

Obtaining voters

Meanwhile, Obama drew millions of voters who latched on to his message of change. The first black candidate of a major US party obviously promises plenty of that, but a not-too-subtle subtext of his change message was that he'd consign the Clintons to history. The fatigue with Bill and Hillary within the Democratic Party has always been known; but it lay dormant until the right candidate came along to energise it. Only now have we seen its extent.

However, if the rush of 'super delegates' to Obama's side on Tuesday night struck the knockout blow to Mrs Clinton's campaign, she didn't actually admit defeat. She may be down, but she's not out, at least not yet. In that respect, she's like the boxer who loses a decision on points, but insists that she was the better fighter.

Even if she does deliver a concession speech, she retains the capacity to make or break Obama's campaign. That presents Mrs Clinton with what may be the biggest dilemma of her life - bigger even than sticking with Bill the day Monica's dry-cleaning bill turned up (a decision she must have occasionally questioned these last few months, since her husband apparently did her campaign more harm than good).

With her substantial delegate count, Mrs Clinton could still hope for a last-minute catastrophe to befall Obama, then reinject herself into the race. But that seems a lost cause.

Clinton's next chance

Her next best shot at the presidency is to hope Obama loses this autumn's election, giving her another crack in 2012. At the same time, she cannot appear to be aiming for that outcome. She has to find a way to be gracious in defeat.

Her best hope may therefore be to run as Obama's vice presidential candidate. Either way, she wins. Should he go on to victory in November, she would still make it into the White House (even if only in a side-office). And should he lose, she would have the luxury of saying "I told you so."

My own opinion remains that with Bill Clinton out pounding the pavement for it, Obama-Clinton would be a dream ticket ... for the Republicans. The paradox is that Mrs Clinton probably can do Obama the most harm by throwing all her weight behind him.

The Obama camp is understandably reluctant to invite Mrs Clinton to run with him. Having campaigned for change, a return to the past will hardly fit the bill. But many party insiders apparently feel that Mrs Clinton has built up enough support to have her way. If she wants the job, he'll be hard pressed to turn her down.

So even though Obama formally launched his campaign against Republican nominee John McCain on Tuesday evening, it's unlikely he's done with the Clintons just yet. Far from it: her role in this race has been altered, but hardly ended.