Why is it that politics has such a problem with lipstick? Since when did this simple stick of colour, kept in a tube and carried in every woman’s handbag, become the mask of dirty swine?

Sure, Sarah Palin wears lipstick, but she’s no pig. Yet for a confounding moment this week, it seemed as though Barack Obama was suggesting she was.

With Palin’s sassy line about lipstick being the only difference between a hockey mom and a pit bull still reverberating from last week’s speech, Obama’s statement on Wednesday, ”You can put lipstick on a pig, but it’s still a pig”, stuck like a nasty fishbone in the throat.

What’s so deceptive about lipstick that it can fool a man into believing those luscious lips he’s eyeing are in fact the pucker of a pig?

Mesopotamian women were using lipstick with all its apparent pig- masking powers – some 5000 years ago. Which is about 1000 years before Sarah Palin believes dinosaurs were roaming the world, according to Hollywood golden boy Matt Damon.

Damon has hit cyberspace performing as an earnest young American man in distress over the rise of Governor Palin. ”I think there’s a really good chance Sarah Palin could become president, and I think that’s a really scary thing,” Damon bemoans to an unseen interviewer in a video clip posted on YouTube. He’s of the view that John McCain – Palin’s less famous handbag – is too old and physically dodgy to last a full term, and so Palin will inherit the Earth, and the US presidency.

Damon likens the Palin phenomenon – the rise of a PTA mom to become mayor, then governor and suddenly president of the free world – to a really bad Disney movie.

And he’s right. It would be a dreadful B grade, cheesy movie, if it were that simple. But it’s not.

Palin’s enormous appeal demands serious scrutiny. Yes, she is neat, trim and exceptionally good on television. And yes, her huntin’ credentials and sexy librarian looks might make otherwise intelligent men have their legs turn to spaghetti and their minds to mush (oh, Nicholas Stuart, we must have a talk). But it’s her appeal to women that is perhaps most startling. And most interesting.

As Lesley Russell expertly explained on this page on Thursday, women voters are pivotal to November’s presidential election. More American women than men vote; more are swinging voters; and US history shows a majority of women usually choose the winner.

What women are getting in Sarah Palin is something no presidential or VP candidate has offered before: on the face of it, a sweet simplicity and neighbourly appeal. Even women who adored Hillary Clinton wouldn’t for a moment assume she could move in next door, much less lean over the back fence while hanging out the washing to have a good chat. Clinton was, and no doubt still is, a career politician made of steel, who clearly owned the political space in which she strutted.

Palin, on the other hand, gives all the appearance of an eager and chirpy young woman who just happened to find herself on stage. Those bright red, shiny, patent leather pumps she wore on Thursday when greeting a 15,000 strong crowd chanting her name are proof she’s basking in her new-found spotlight, and fully intends to enjoy it. She looked a bit like Dorothy standing before the singing Munchkins in the land of Oz, and you couldn’t help but wonder when she might start clicking those heels.

Palin manages to give the impression of innocent ambition, almost as if she has just stumbled upon stardom while going about the worthy business of being a mom and caring for her Down syndrome newborn. Evident ambition in a woman, such as Clinton, has a certain stench that seems to frighten ordinary folk. Palin may indeed be extremely frightening when you get to know her and where she stands on crucial issues, but seen only at a distance on the presidential campaign big-screen, she is far from frightening. Palin appears clean, good, virtuous, loving and loyal. Whether she is or not isn’t the point. In politics perception is primary. And on primary perceptions Palin is a marketing dream.

The movie critic Roger Ebert has likened her to an American Idol candidate. She’s got that good- looking, sunny personality, and hard working ethos of the fierce competitor. But most importantly, like the Idol wannabe, Palin has that hometown rawness that ordinary people identify with. ”They think, ‘Hey, that could be me up there on that show!”’

Perhaps that-could-be-me appeal is why so many women were shocked and appalled by Senator Obama’s lipstick-on-a-pig comment. The moment I heard it and choked, I assumed he’d be quick to apologise. But, far from sorry, Obama ramped up claims of phoney outrage, and even repeated the line the next day.

‘Lipstick on a pig’, it turns out, has long been part of the American political lexicon. It’s even the title of a book by a former Pentagon communications chief. It was a favourite saying of Dick Cheney’s, and in May John McCain told an audience he didn’t like the saying, but went on to use it anyway – several times. John Edwards’s wife used it, just months ago. So did a Republican fundraiser when complaining about the party’s lack of funds. ”There’s no use putting lipstick on a pig.”

But why lipstick? Can painted gloss be that blinding? Or are those men who believe they can be deceived by a woman’s lipstick really just as thick as swine?