NICOLA STURGEON has led the SNP to a record third term in power at Holyrood as a surge in support for the Scottish Conservatives saw them overtake Labour to become the main party of opposition.

In a dramatic night of results, Tory leader Ruth Davidson secured a shock victory in Edinburgh Central as her party won 31 MSPs - by far its best result ever at the Scottish Parliament and up from 15 in 2011.

Ms Sturgeon's party won 63 of the 129 seats that were up for grabs, failing to secure a second overall majority.

READ MORE: Video - Nicola Sturgeon hails historic third term for SNP as Labour endures new losses

The SNP ended up with six fewer MSPs than the record 69 the party won under Alex Salmond in the 2011 landslide.

Labour endured another disappointing result, with the party securing 24 seats - a drop of 13 from the party's total five years.

David Cameron tweeted his congratulations to Ms Davidson on the Tories' "historic result".

He added: "She is a leader who will stand up to the SNP and give Scotland strong opposition."

Scottish Labour leader Kezia Dugdale said she was "heartbroken" the Conservatives had overtaken her party - which once dominated Scottish politics - to claim second place in the election.

Last May the party lost all but one of their MPs from Scotland as the SNP swept the board in the general election.

READ MORE: Video - Nicola Sturgeon hails historic third term for SNP as Labour endures new losses

Ms Dugdale said after that result "this election was always going to be tough for the Scottish Labour Party".

She insisted she would remain as leader adding: "I am proud that our campaign rose to the challenge of offering an alternative vision of what could be done in our new, more powerful parliament."

With the constitution now the dominant issue in Scottish politics, she said her "determination to try to move the Scottish debate on" from the arguments of the 2014 independence referendum had cost Labour votes.

She backed income tax rises for not just the wealthiest Scots but basic rate taxpayers, saying this was needed to prevent cuts in public services such as schools and the NHS.

Ms Dugdale added: "There's no doubt that our defeat for the Labour Party is painful but it is not the end of our campaign.

"We will continue to argue for Labour values, Labour ideas and Labour principles.

"The work to renew the Scottish Labour Party so it is fit to serve the people of Scotland continues."

READ MORE: Video - Nicola Sturgeon hails historic third term for SNP as Labour endures new losses