NICOLA Sturgeon has urged SNP members to focus on winning an unprecedented hat-trick of Holyrood elections, as the party heads to its annual conference this week against an unexpectedly turbulent backdrop.

Looking ahead to the biggest gathering in the SNP’s 81-year history, the First Minister last night said the party was within reach of an historic third-term at Holyrood.

She said the three-day meeting would be a launch pad for next May’s elections, and said the party would “keep our eyes on the prize of a third term”.

With membership up from 25,000 to 112,000 since the referendum, a record 4700 delegates will be at the Aberdeen Exhibition and Conference Centre from Thursday to Saturday.

A poll last week put the SNP on course to win a second overall majority in 2016, with support for the party at 56 per cent, a massive 35 points ahead of Labour on 21 per cent, the Tories on 12 per cent and the LibDems at 6 per cent.

However in recent weeks the SNP has been hit by revelations around the business history of suspended Edinburgh West MP Michelle Thomson.

It emerged that her solicitor, Christopher Hales, was struck off last year over 13 property deals involving Thomson or her business, M & F Property solutions.

Some deals saw homes bought from financially distressed owners at knock-down prices then sold at a profit the same day - such back-to-back transactions have been linked to fraud.

The Scottish Solicitors’ Discipline Tribunal said Hales, who is now the subject of police enquiries, must have been aware that he might have been “facilitating mortgage fraud”.

Culture Secretary Fiona Hyslop has been under fire for alleged cronyism after awarding a £150,000 grant to the promoters of T in the Park while they employed an ex-SNP aide.

Last week the SNP lost its first by-election since the general election, with the LibDems picking up the Highland Council seat vacated by the new Inverness MP Drew Hendry.

Despite the inauspicious run-up to conference, Sturgeon said the SNP would be “very proud to stand on our record next May”.

She said: “The SNP are now firmly established as a major force in not just Scottish but UK politics, where we provide the real opposition to the Tories at Westminster in the absence of a united or credible Labour Party.

“That is an election we intend to win, and win with an outright majority – something which is supposed to be impossible in a PR system but something we have already done once.

“To win a majority again will not be easy, and I take absolutely nothing for granted. But we have the people, the policies and the momentum to carry us forward to another election success next May.

“Winning a third term would be historic and unprecedented, making the SNP the first party since devolution to win three successive Holyrood terms in office."

Her opponents said the SNP's record should be a warning against a third term.

LibDem leader Willie Rennie said: “We have a recruitment crisis in our NHS, we have seen massive cuts to college places and falling literacy levels in our schools. Scotland can't afford another five years of the SNP."

Tory MSP Alex Johnstone added: "The SNP clearly sees itself as being in a strong position, but it had that arrogance ahead of the referendum too.

"And with both Labour and the Lib Dems a busted flush, the only pro UK option for voters is the Scottish Conservatives."

Labour said the country needed "a strong team of Labour MSPs so the SNP don't have it all their own way".