Howard backs adviser in battle for Downer's seat

Mr Briggs, who advised Mr Howard on industrial relations and communications during the last term of the Howard government, is one of nine Liberal candidates contesting preselection for Mayo, which will be held on Sunday.

Mr Howard is understood to be unhappy that Mr Briggs's association with the Work Choices legislation has been used against him by other Liberals in the heated contest for the safe seat, vacated on Monday by the former foreign affairs minister. In a rare move, Mr Howard wrote a lengthy letter supporting Mr Briggs and agreed to have it distributed yesterday to the 550 preselectors in the Adelaide Hills-based electorate.

Mr Howard describes Mr Briggs as "an energetic, intelligent and high-calibre adviser" and defends his work on industrial relations.

"His earlier experience in working for an industry association gave him a good understanding of business realities, especially those affecting small business," he says.

"Due to this background, he came to his position in my then office, well grounded in the details of industrial relations law."

Mr Howard says he was "struck by the speedy manner" in which Mr Briggs comprehended the details of his communications role.

The letter will stir what is already a lively contest.

Mr Briggs's main rivals are: Iain Evans, a former South Australian state opposition leader; Matt Doman, a former staffer to Nick Minchin; and David Basham, a dairy farmer. Mr Basham is being backed by the moderate faction loyal to the federal frontbencher Christopher Pyne.

Mr Downer and Senator Minchin, both factional enemies of Mr Pyne, have made pointed statements against Mr Pyne and Mr Basham, saying a safe seat such as Mayo should be held by someone who is frontbench material.

Mr Downer is understood to be favouring Mr Briggs. Labor is unlikely to contest Mayo.