Could a six-year-old s-x scandal really bring Julia Gillard’s minority government undone?

Liberal Party powerbrokers, aware that one by-election defeat would tip Labor out of office, believe it’s a real possibility.

They believe it’s especially promising given that Labor MP Craig Thomson is under fire for admitting last week that he approved thousands of dollars worth of payments to a Sydney escort agency when he was boss of the Health Services Union.

Thomson is the member for Dobell – a marginal electorate on the NSW Central Coast – and the Libs are keen to settle on a candidate soon so they’ve got someone ready to go if he falls on his sword.

“In the current climate, the seat would fall,” a well-known NSW Liberal factional boss told The Power Index today. “But we have to find a good quality candidate.”

The powerbroker says Thomson will have to go if he’s found to have acted inappropriately by any of the many audits or inquiries looking into his conduct as head of the HSU.

“He’s been humiliated, his reputation is seriously damaged. Yet he’s been able to hang in there until now.”

Tom Switzer, former opinion editor of The Australian and former adviser to Brendan Nelson, is among those who have been asked to run in Dobell.

Switzer told The Power Index today that he was seriously tempted to take up the offer, but had to refuse because of work and family commitments.

“I think it would be a wonderful opportunity to bring down the government over the issue of the carbon tax, which is very important for me,” he said. “You’d go down in history as a pretty significant figure because you’d helped stop the carbon tax.

“I was flattered to be asked but I’m out.”

Switzer, who lives on Sydney’s North Shore, says he already has plenty on his plate as editor of the Spectator Australia and lecturer at the University of Sydney.

The industrial umpire, Fair Work Australia, is currently investigating the allegations against Thomson. Senior Liberals, including George Brandis and Andrew Robb, are pushing for a criminal investigation.

The MP has repeatedly denied he had any knowledge that the money he authorised was being spent on prostitutes.

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