The Holyrood election will bring about a "seismic shift" in Scottish politics which could see the Tories form the official opposition, Scottish Secretary David Mundell has predicted.

Mr Mundell, who is the only Conservative MP in Scotland, said he is "confident" the party will achieve its goal of becoming the second largest party in the Scottish Parliament.

That would be the Tories' best ever Holyrood result and a dramatic transformation for the party.

In 1997, the same year that Scots voted overwhelmingly in favour of the creation of the Scottish Parliament, the Conservatives were wiped out north of the border in the general election.

Scottish Conservative leader Ruth Davidson said her party "might be in for a very good night indeed".

Asked if she is confident that her party will come second, she said: "I said yesterday that I thought that our nose was in front, all the indicators tonight seem to confirm that.

"We've seen our vote double in several areas across the country, including places like East Kilbride and places like Kilmarnock that aren't traditional Tory strongholds.

"We're hearing particularly in the north-east that we may well go from two to four MSPs, so we've got a lot to look forward to tonight I hope."

The Herald: Leader of the Scottish Conservatives Ruth Davidson with deputy leader Jackson Carlaw in Edinburgh, Scotland, ahead of the Scottish Conservative party conference

Jackson Carlaw, the Scottish Conservative deputy leader, won the Eastwood constituency on the outskirts of Glasgow from Labour's Ken Macintosh.

Mr Macintosh, who had held the seat since 1999, came third behind the SNP.

Meanwhile, Scottish Tory John Scott held on to the Ayr constituency.

As the results came in, Mr Mundell said he is "confident we can achieve our objective to become the official opposition in the Scottish Parliament".

He told BBC Scotland: "That will be good for Scotland, good for the Scottish Parliament, Ruth has demonstrated throughout this campaign that she is the one politician that can go toe-to-toe with Nicola Sturgeon, that she can stand up to demands for a second referendum.

"She can also scrutinise the SNP and make sure they deliver on promises they have made on health, on education, and I think by doing that we will get better government, and that will be good for everyone in Scotland."

READ MORE: Live: Scottish election 2016

He added: "I think it will be a seismic change in Scottish politics that the Scottish Conservatives are the second party in the Scottish Parliament.

"I was a candidate back in those first elections in 1999, it would have been incredible to think the Scottish Conservatives could have finished ahead of Labour and be the official opposition.

"It demonstrates that Ruth has transformed our party in Scotland, taken it forward and given us, I hope, a very significant role in the next Scottish Parliament."