HILLS councillor Robyn Preston and the former Mayor of Parramatta, Tony Issa, are among a raft of personalities to challenge the leader of the Liberal Party's Christian far Right, David Clarke, for his seat in the NSW Legislative Council.

As the News revealed last week, the push to topple Clarke, 64, is being led by his former employee and now Federal Member for Mitchell, Alex Hawke.

Hawke has reinvented himself as leader of the so-called ``soft Right'' and is backing Hills resident David Elliott, the chief executive officer of the Civil Contractors Federation (NSW).

Elliott is tipped to win the eight-year appointment to the upper house.

Failing this, he will contest the state seat of Riverstone, held by Labor's retiring MP, John Aquilina.

Two weeks ago so concerned by the on-going war between the rival Right powerbrokers federal Opposition leader Tony Abbott intervened.

Although he met Hawke privately the stoush continues unabated, despite state leader Barry O'Farrell endorsing David Clarke.

When preselection closed for what the party calls the metropolitan north-west province last Thursday, Clarke the man regarded by many insiders as the Liberal Party's most powerful king-maker looked likely to lose his seat on February 20.

He is relying on the support of the Left leader, Michael Photios, a former state MP, to swing his faction behind him.

This is ironic, since Clarke supporters have helped topple several left-wing politicians in recent years.

Understood to have nominated for Clarke's job are David Elliott; solicitor and Hills Shire councillor Robyn Preston; Blacktown Councillor Nick Tyrrell, former Parramatta Lord Mayor Tony Issa; dumped Blacktown Young Liberals president Keith Topolski; and Mark Chan, a Parramatta councillor who unsuccessfully ran for Bennelong.