A few months before Australia's conservative Liberal Party suffered its worst election defeat last May, Sydney stockbroker Angus Aitken donated $A230,000 ($NZ280,000) to the party, a political cause he thought he would support for life.

This year he is changing teams, committing $A1.1 million to populist anti-immigration party Pauline Hanson's One Nation as he turns away from a conservative establishment racked by infighting and dismal polling.

Aitken is not alone: encouraged by mining billionaire Gina Rinehart, some of Australia's wealthiest voters are shifting support from the Liberal-National coalition to an outsider party that has, until recently, relied on small donations.

Since launching in 1997, One Nation has had only a peripheral presence in parliament with its hardline anti-immigration stance and antagonism toward environmental and progressive social issues.…