-- PHOTO: REUTERS

The gut feel grows, until the voice in your head triggers that moment of liberating epiphany: 'This is it.'

Mrs Hillary Clinton is not there yet.

'We're not big on quitters in this family,' said husband Bill. Thus, this indestructible presidential hopeful refuses to concede to Mr Barack Obama in the race for the Democratic nomination. The mathematics is against her. The money for her campaign is drying up.

'We're flying against the wind. But that's the story of my life, fly against the wind, you'll get there eventually,' she said breezily last Friday.

Die-hard fans are in awe of her indefatigability, saying that this is the resilience one needs in spades to stand up to the impending Republican onslaught, and then to serve as commander-in-chief of the world's sole superpower.

However, even among her erstwhile supporters, many acknowledge that unless she throws in the towel soon, she will damage irreparably the Democratic Party's chances.

But Mrs Clinton is not the first politician, and will not be the last, to find it hard to quit.

There are exceptions: politicians who opt for a graceful exit. Mr Bill Clinton's vice-president, Mr Al Gore, was one. After the presidential election of 2000, he smilingly accepted a Supreme Court decision that many found dubious.

He withdrew from politics, dabbled in academia and then re-emerged as an environmentalist. His Nobel Peace Prize was confirmation of the old adage that when one door closes, another opens.

But then again, history might judge that his country and the world might have been better off if Mr Gore had had a smidgen of the Clintonesque fighting spirit and won the battle for the White House. After all, a President Gore probably would not have taken his country into the ill-judged Iraq War. So, who is to say whether the reverse is always better than the forward gear.

Certainly not most politicians, who need to be told to leave, and often need more than a nudge. It's not surprising really. After spending your whole political life persuading the public that you are special, how do you then tell yourself that you are dispensable?

In Zimbabwe, Mr Robert Mugabe is clinging on to power using every trick in the book. In Cuba, only his failing health could persuade Mr Fidel Castro to step aside after half a century in charge. Mr Silvio Berlusconi has been in and out of Italy's top job twice before and is back for more, this time with newfound vigour and a refreshed face, the result of what surgeons suspect is a facelift.

In Malaysia, the interventions of private citizen Mahathir Mohamad have been a nasty thorn in the side of his successor. Again, history will judge whether or not Malaysia benefited from having an active and opinionated former premier who refused to quit public life.

As with most other things, Singapore's own approach is unique. With both former prime ministers remaining in Cabinet, any differences of opinion can be thrashed out behind closed doors. Mr Lee Kuan Yew has never pretended to be the type who could retire to a life of golfing and quiet meditation. But not for Singapore the open competition between leaders of the past and present.

The system prizes cohesion above all. Everyone who can contribute is kept within the team.

But it's not just the political system that determines whether and when politicians quit. It's clearly also psychology. Something within distinguishes the Al Gores who contentedly concede even when supporters are goading them on, from the Hillary Clintons who cannot back down when even friends are urging them to.

Considering the public humiliation she had to go through when her husband's adulterous affairs were exposed, she probably doesn't lack the steel for this present struggle.

There is another compelling psychological theory. Nicholas Kristof of the New York Times wrote last week that one of the reasons she is still fighting is 'a resentment that she and many of her followers feel over sexism in the campaign'.

He noted: 'One of the political lessons of this year - backed by psychological research and polling data - is that the bar is probably higher for a woman candidate for president than for a black candidate.'

Last Thursday, she said tellingly to a crowd: 'Do you know how difficult it is for women to say we're the best at anything?'

Perhaps that explains the enigma that is Hillary: She is overcompensating for the burden of her gender. No doubt, if she had given up too early, many would have said, 'What did you expect? She's just a woman.'

Everyone, even women, would have come away feeling that the natural order of things had been restored - women are supposed to be first ladies, not presidents.

Men can quit without appearing weak: A gracious concession can even be a sign of inner strength. Can a woman give up without being seen as anything other than the weaker sex? So far, Mrs Clinton is not inclined to find out.

You go, girl.

zuraidah@sph.com.sg