IT'S a refrain often heard at Tory party functions: ''If only Betsy were leader, we'd be miles ahead of Labour.''

Elizabeth ''Betsy'' Duncan Smith, or BDS as she is known in Conservative circles, is the doll-like, ever-smiling spouse of the man with the worst job in British politics.

The camera loves the 42-year-old Betsy in her Chanel two-piece suits and pearl necklaces that ooze the ambience of London's well-to-do Sloane Square.

Like Ffion Hague and Norma Major before her, the spouse of the Tory leader is very often seen but never heard. ''Always present but never there'', as the late Denis Thatcher once said of his role.

Asked at a party conference how she liked being the wife of the leader of the opposition, she turned quickly to Nick Wood, IDS's spin doctor, and asked feverishly: ''What do I say now, Nick?''

Betsy Wynne Freemantle was educated at St Mary's School at Wantage, Oxfordshire, before moving to Stowe School, but left at 17 to work for a spell at Harrods and then become a secretary.

Moving in the same military circles, she met her future husband at a party in London, and in 1982, aged 23, she married her Scots Guards captain and five years later gave birth to Edward, the first of four children. Alicia, Harry, and Rosanna followed.

A distant cousin of the late Princess of Wales, she is from true blue landed stock, being the daughter of the 5th Baron Cottesloe, a former commander in the Royal Navy and an ex-Lord Lieutenant of Buckinghamshire.

For the traditionalists of the Chingford Conservative Association, BDS was the model Tory wife - ultra-loyal, photogenic, blue-stockinged, and with an aristo background to boot. ''She is an absolute rock,'' one Tory proudly noted.

Lady Cottesloe once remarked that her daughter was ''totally absorbed'' by her family and was ''certainly not political''. She added: ''I don't even think she has any hobbies.''

It is an irony then that arguably her only brush with the world of party politics is the time she spent as her husband's diary secretary, the subject to which Sir Philip Mawer, Westminster's standards watchdog, will now turn his mind.

Above all else, Mr Duncan Smith, fiercely protective of his family, will be hurt to the core that his wife has become the centre of attention of the Westminster newshounds.

He once noted: ''Having watched my wife looking after four children and running a home, I know she is not my equal, she is my superior.''

Indeed, like most politicians' wives, Betsy is her husband's sounding board and closest adviser. A friend once noted: ''She's the sort of person who would be very good in a crisis - tremendously calm.''

If ever there was a week when IDS needed his wife's clear head and steady nerve, this is it.