Turnbull, do a Dame Nellie Melba in Wentworth

DESPITE his critics wanting to relegate Malcolm Turnbull to the dustpan of political history, the member for Wentworth may wish to consider the Dame Nellie Melba option. Party powerbrokers should hope he does remain in federal politics. Indeed, rather than dumping on Turnbull for his past mistakes, Liberals ought to be asking him to stay.

The reason is simple. Turnbull is the Coalition's best hope for retaining the now marginal seat of Wentworth in Sydney's east.

We all know the Wentworth story. Australia's smallest electorate. Home to the nation's wealthiest suburbs. One of the original 75 seats at federation and one of only two seats to be held by conservatives throughout its history.

Then the blue-ribbon seat turned dangerously marginal after a series of redistributions stretched its boundaries to include the more politically diverse areas of Kings Cross, Potts Point, Woolloomooloo and parts of Darlinghurst. Gays, straights, greens on bicycles, gas-guzzling SUV drivers, bleeding hearts, economic hardheads, corporate high-flyers complaining about high taxes, homeless drunks bumming a cigarette, the uber-rich, the extremely poor and everyone in between.

Welcome to contemporary Wentworth.

Writing before the last election, Shane Easson, responsible for the Labor Party's redistribution submissions, released an analysis headed: "Wentworth: Turnbull's Darkness At Noon."

Easson concluded that with a declining margin, "unless Turnbull can buck the trend we can expect Wentworth to become a seat usually won by the ALP".

Turnbull did buck the trend. Sitting on a margin of just 2.5 per cent, the member for Wentworth attracted a further 1.3 per cent swing towards the Liberal Party, a record swing for the Liberals when voters otherwise sent John Howard packing.

After his turbulent time as Liberal leader, many within his own party were relieved when Turnbull announced his decision to leave federal politics.

Many quite rightly disagreed with him over the Coalition's climate change policy. Many quite rightly questioned his rash judgment over the Godwin Grech affair. Others were simply envious; Turnbull's career successes reminded them of their own mediocrity. Hence their palpable sense of schadenfreude.

But the biggest smiles were found within the Rudd government. Minus the Turnbull name, Wentworth immediately became more winnable for Labor.

Steven Lewis, a candidate for Labor preselection, a lawyer with Slater and Gordon, long-time ALP member and lifelong resident of Wentworth, is hoping to make ALP history by making Wentworth Labor.

Of course, there will be a long list of Liberal contenders for Wentworth when Turnbull leaves parliament. Many impressive. Some not. Importantly, none of them have Turnbull's gravitas, nor the cross-sectional appeal that he has proven he can muster from an eclectic electorate.

Put it this way. Only Turnbull will wipe the smile off federal Labor by deciding to recontest the seat at the election later this year.

If Turnbull stays on, he may buck another trend. If he learns from past errors, he may become the most formidable politician to hold Wentworth.

For a seat that started out as the jewel in the Coalition crown, Wentworth has not produced any longstanding sparkling performers. For 50 years the seat hosted the first deputy leader of the Liberal Party (Eric Harrison) and the politician who introduced the first home owners grant (Les Bury). Remember them?

After that, politicians have come and gone. Most short-lived. Most hardly leaving a mark that history will remember for the right reasons.

John Hewson, best known for his bitterness, lasted eight years. Peter King, famous for being ousted by Turnbull, lasted three years.

Wentworth is yet to produce a Robert Menzies or a Howard. Perhaps the marginal seat now dubbed a poisoned chalice will never produce a Liberal prime minister. But don't bet on it when it comes to Turnbull.

If he decides to stay, the former Liberal leader could prove that his flaws are neither fatal nor final. He can tame his famous impatience and curb his arrogance. He can learn that politics is about carrying members of the party with you, rather than putting them down.

Which brings us to the challenge of climate change.

Turnbull liked to talk about Margaret Thatcher. But Thatcher is not famous because she talked about climate change. Thatcher is famous for convincing British voters to support major reforms. She remained in power for so long as she was careful not to let her arrogance move too far ahead of public opinion.

As Liberal leader, Turnbull's mistake was to be more committed to an emissions trading system than his own party, not to mention the Australian electorate. In fact Turnbull was more committed than Prime Minister Kevin Rudd. While Rudd has spent 2010 backing away from the ETS, barely mentioning it in public anymore, Turnbull continues to do so.

If Turnbull is serious about returning to politics, he will need to modify that position.

That does not mean morphing into a climate-change sceptic.

But at a time when even US President Barack Obama is moving away from cap and trade, it

makes no political sense for Australia to embrace it.

If Turnbull cannot accept that political reality, then perhaps he is best joining the ranks of the past.