Australia's richest politician, Malcolm Turnbull, was elected leader of the conservative opposition yesterday but analysts said he would struggle to end the disunity plaguing the Liberal Party after its worst-ever election defeat last year. The leadership vote, called by former leader Brendan Nelson on Monday night, took everyone by surprise, including his shadow cabinet. The move ended months of leadership speculation, fed by bad polls and the refusal of former Howard government treasurer and deputy leader Peter Costello to say when he would leave Parliament. Rumours that Mr Costello would stand for the leadership reached a crescendo in the lead-up to the publication of his memoirs this week. When Mr Costello finally revealed he was not interested, expectations mounted that Mr Turnbull would mount a challenge. Dr Nelson initiated the leadership ballot in a bold bid to head off the move after nearly 10 months of poor polling, with his rating as preferred prime minister hovering around 17 per cent. He lost the party ballot in Canberra by 41 votes to 45. He last faced off against Mr Turnbull, the federal member for the seat of Wentworth - home to Bondi Beach - after the Liberal Party's devastating loss, winning by a narrow margin of three votes. Peter van Onselen, a professor of politics at Perth's Edith Cowan University and author of John Winston Howard: the Biography described the ascension of Mr Turnbull, a former Goldman Sachs Australia chairman, as inevitable. 'The fact Nelson called the spill was not a mistake. He really was a dead duck. If he had won it he could have had six months of breathing space to cement himself in the job. He needed that because his leadership was really under pressure and he was likely to get rolled in the next couple of months anyway. He was counting on winning and getting six months without Malcolm breathing down his neck.' He said while Mr Turnbull would have a better chance of success than Dr Nelson, he was not sure either was well placed to win the next election in 2010 from Prime Minister Kevin Rudd's Labor Party, which swept to power in November, ending almost 12 years of Liberal/National coalition rule. 'Mr Turnbull's ... [upper crust] image will not play well with John Howard's mortgage-belt battlers and I doubt the moderate small 'L' liberals who abandoned the party in the Howard era will return quickly.' Professor van Onselen, a leading commentator on Liberal Party politics, said it was unlikely the development would end internal disunity. 'It's the end of it for six, maybe 12, months. If Peter Costello does not leave Parliament and Turnbull does not poll well, rumours about a Costello leadership will continue,' he said. 'I think this is just a suspension of hostilities and could be brief if the polls don't turn around. Remember the lamest-duck leader in a long time only lost by four votes to someone with an incredible CV. 'That result should have been 65-21 because Nelson hasn't been a strong traveller. That's a strong indication of how polarised the Liberal Party is. The 'anyone but Malcolm faction' is alive and well in the Liberal Party.' Former Liberal leader John Hewson agreed, saying the big challenge was to unite and rebuild the party. 'Turnbull now has his chance and he'll need to prove himself by reuniting the party and coming up with good policy. And there'll be two people on the backbench who are potential alternative leaders, Nelson and Costello,' Dr Hewson said. 'I feel a bit sorry for Brendan because he wasn't given a free run, especially with all that Costello distraction over the last couple of months. The media was absolutely infatuated with Costello and was really tough on Nelson, an unknown against a popular new prime minister,' he said. 'And there was also instability generated on the backbench by the Turnbull supporters. Brendan felt he could not sustain that so he opted for a pre-emptive strike.'