NEW Liberal Member for Mayo Jamie Briggs will have his work cut out for him during the next 18 months to increase his party's popularity in the electorate after claiming a narrow victory in the seat this week over the Greens.

With nearly 80 per cent of the by-election votes counted on Wednesday, the Liberals sat on 53.12pc in a two-party preferred vote, despite suffering a 10pc swing on primaries.

Labor had opted not to run a candidate.

Flinders University School of Politics Associate Professor Haydon Manning said the swing against the Liberals would not go unnoticed.

"The Liberals bear the burden of 10 years in government without addressing the issue satisfactorily," he said.

"And Labor didn't run a candidate to give voters an option so voters registered a protest vote with Di Bell and The Greens."

* Extract from a full report in Stock Journal, September 11 issue.