Relentless is one of the kinder words that Republican opponents use to describe Nancy Pelosi, tipped to become the first Madam Speaker in American history, should, as polls suggest, the Democrats gain control of the House of Representatives in elections next week.

If coming under sustained attack is the sincerest form of flattery in politics, then Pelosi must be thrilled indeed as polling day draws near. She certainly shows none of the brittleness that has sometimes scuppered women seeking high office as she stumps around the country, usually in a trademark lilac suit and sporting a dazzling smile of surprising sincerity (she denies having had a facelift).

Increasingly, Republicans have been tuning their national campaign to paint Pelosi as the worst kind of wicked witch from the West, a tax-and-spend liberal from San Francisco, a city she has represented for nearly 20 years. As one commentator put it, the strategy has been to portray her as “the pariah from central casting”.

True, that bastion of alternative culture is the crucible for much that the Right finds abhorrent. But on occasion Pelosi has supported policies put forward by President Bush, leading some to think that this self-proclaimed “Italian-American grandmother” is more a pragmatic moderate than a driven liberal. However, she does support a quick exit from Iraq, gay marriage and reducing tax cuts, although you might be hard pressed to know. Her language these days is larger on imagery than detail about what might happen if Democrats regain power and start to make life very hard indeed for Bush. There is much talk of “civility in terms of how we discuss our ideas and fiscal discipline” and a need to “drain the swamp that is Washington”.

Still, it would be sweet victory for the 66-year-old mother of five about whom few had heard until commentators started to wonder at the discipline with which Democrats have prepared themselves under her leadership.

The theatre of politics requires even the most ambitious to show some signs of reluctance. Pelosi is no different, implying that politics was an afterthought to bringing up the children she had with her husband, Paul, a property multimillionaire whom she married in 1963.

The evidence suggests otherwise, with drive and ambition rather redundant words to describe somebody who, by all accounts, was plotting a political career as a child when her father was Mayor of Baltimore. He taught her how to count votes the way that others learn merely to count. By the age of 7, she told one interviewer recently, she was fielding calls from constituents. “Every day was a campaign,” she said of her childhood. It still is.