Mayo opinion poll shows Rebekha Sharkie is the clear frontrunner against Georgina Downer

The race for Mayo is shadowed by two titans of SA politics — will Xenophon protege Rebekha Sharkie hold her seat or could Georgina Downer continue her father’s legacy? A new Advertiser poll has the answers.

Rebekha Sharkie and Georgina Downer are battling for the seat of Mayo for the second time in less than a year. Sharkie became Centre Alliance's sole Lower House MP when the fledgling party was in the ascendancy under former leader Nick Xenophon — while Downer's father Alexander held Mayo for the Liberal Party from 1984 to 2008. Art: Rebecca Fletcher

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The almost-150-year-old Downer political dynasty is imperilled by a disastrous Advertiser opinion poll result for Liberal Mayo candidate Georgina Downer, who is heading for another thrashing by popular Centre Alliance MP Rebekha Sharkie.

In a potentially fatal blow to the well-credentialed Ms Downer’s political ambitions, the Advertiser/YouGov Galaxy poll reveals an almost-identical result to last July’s by-election result, which Ms Sharkie won with 57.5 per cent of the two-party preferred vote.

The poll of 557 voters in the Adelaide Hills, Fleurieu Peninsula and Kangaroo Island electorate shows Ms Sharkie’s primary support has fallen by a little more than one percentage point to 43 per cent, while Ms Downer’s has risen slightly to 38 per cent.

Ms Sharkie, who last weekend was prominently backed by her one-time mentor Nick Xenophon, leads the two-party preferred result with 57 per cent to Ms Downer’s 43 per cent — an almost mirror image of the 57.5 per cent to 42.5 per cent result last July.

The United Australia Party, led by billionaire Clive Palmer, registered 3 per cent primary support, much lower than the 9 per cent in an Advertiser Sturt poll published last week.

This indicates Ms Sharkie, at least, has been able to withstand his $50 million advertising campaign aimed at voters disillusioned with the two major parties.

The poll was taken on the evening of May 2 — the same day Ms Sharkie was facing questions over when she knew about police investigating a campaign volunteer later charged with allegedly stalking Ms Downer.

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Senior Liberals have predicted Ms Downer would be supported to stand again in Mayo if there was a close result at the May 18 election, or backed for a Senate spot if she secured a sizeable swing in the Liberals’ favour.

But if the Advertiser poll results are reflected at the election in less than a fortnight, senior Liberals are warning Ms Downer might not even have sufficient support to become a Senate candidate.

If her fledgling political career was torpedoed, this would end a 141-year-old South Australian political dynasty started in 1878 by her great-grandfather, Sir John Downer — twice SA premier and a senator in the first federal parliament.

Ms Downer’s father, Alexander, held Mayo for 24 years from 1984 to 2008 and was a federal Liberal leader and Australia’s longest-serving foreign affairs minister, while her grandfather, Sir Alick, was a federal minister.

Senior Liberals from both of the party’s factions rate Ms Downer’s credentials highly — she is a former diplomat at the Australian Embassy in Japan and was a corporate lawyer in Melbourne.

But there is frustration within the party at what is viewed as a successful attack campaign against her, spearheaded at last year’s by-election by pressure group GetUp! and Labor, that portrayed her as a right-wing candidate seeking to assume her family’s birthright.

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Having defeated former Liberal minister Jamie Briggs at the 2016 election under the Nick Xenophon Team banner, Ms Sharkie has become, according to the poll results, a popular local MP.

More than 60 per cent of respondents said they were satisfied with her performance, while 18 per cent were dissatisfied and 19 per cent uncommitted.

She might become a kingmaker in the event of a close result nationally on May 18 but last week declined to answer Advertiser questions on the issue, including whether she would rule out backing Labor in the event of a hung parliament.

Mr Xenophon, a former state and federal upper house powerbroker whose political career imploded at last year’s state election, on the weekend fronted a full-page Advertiser ad urging a vote for his former party, the Centre Alliance.

The result in the Mayo poll, which has a margin of error of 4.2 per cent, raises questions about the Liberal stronghold of Grey, where Nick Xenophon Team candidate Andrea Broadfoot achieved 48 per cent of the two-party preferred vote in 2016.

She is again trying to unseat Liberal Rowan Ramsey and GetUp! is handing out how-to-vote cards backing her, Labor and the Greens, urging people to vote against the Liberals because of the party’s climate change “chaos”.