Nigel Farage's Ukip looks to have won its first seat in Scotland in the European Parliament elections.
Not all the results are in yet, but it appears certain that David Coburn has been voted in as one of Scotland's six MEPs.
Alex Salmond's SNP had been battling to increase their tally of MEPs from two to three - a result which would have boosted the party ahead of September's independence referendum
But with all but one of Scotland's council areas having declared their results, it appeared they had failed to win enough votes to achieve this.
The SNP polled most votes in the European Parliament elections, but have so far failed to increase their share of the vote from the last European elections in 2009.
The Liberal Democrats appeared to have lost their Scottish MEP, following a fall in their support.
With 31 of Scotland's 32 councils having declared their results, the SNP had 386,193 votes, ahead of Labour who came second with 346,377.
The Conservatives were in third place with 230,569, while Ukip - which wants the UK to withdraw from the European Union - came in fourth with 139,687. The Greens beat the Liberal Democrats into sixth place, with the parties winning 107,805 and 95,076 votes respectively.
The final figures will be known later today, when Western Isles Council declares its results.
But the results so far give the SNP 28.9% of the vote ahead of Labour on 25.9%, and the Conservatives on 17.2%. Ukip polled 10.4% of the votes, ahead of the Scottish Green Party, who secured 8.1%, while the Liberal Democrats were sixth with 7.1%.
Mr Coburn, who looks certain to be sent to Brussels as Ukip's first Scottish MEP, vowed his party would "stand up to Salmond and his nasty little dictatorship".
He said: "This result says people in Scotland are as worried about the same things as everyone else in the rest of the United Kingdom.
"We all have the same problems that need to be resolved and, quite frankly, Mr Salmond seems to think that Scotland is so different from everywhere else - well, it's not.
"In England the people are just the same as the people in Scotland, they're just as nice, just as pleasant, and they have the same problems and they need to be resolved."
He said the campaign for Scottish independence is a ridiculous idea.
"I'm a patriotic Scot and, as far as I'm concerned, the union between Scotland and England has lasted for 300 years, and has enabled both countries to punch above their weight, and we have a stable currency - what's not to like about that?" Mr Coburn argued.
"I'd like to see both Scotland and England leaving the EU together and running our own affairs.
"I'd like to see less Westminster and less Holyrood in everybody's lives. I think that would be a good thing for Scotland.
"I want to get the weight of the socialist Scottish state off the back of the Scottish entrepreneur. And, most of all, I want to see every child in Scotland get a thoroughly good education."
Ukip's shock breakthrough gives the Scottish independence campaign a serious problem, he said.
"Ukip are not going to sit down and be quiet like all the other parties," he continued.
At the last European elections in 2009, the SNP and Labour in Scotland both won two seats - with the parties polling 29.1% of the vote and 20.8% respectively. Meanwhile, the Tories and the Liberal Democrats each had one Scottish MEP.
This time round, it appears the Nationalists and Labour will retain their two Scottish MEPs, with the Scottish Tories also keeping their European representative.
But the Liberal Democrats appear to have lost their one MEP, with that seat going to Mr Farage's party, giving them a breakthough in Scotland.
That would see Ian Hudghton and Alyn Smith returned as the two SNP MEPs, alongside Labour's David Martin and Catherine Stihler. For the Tories, Ian Duncan would be elected, replacing long-serving Scottish Tory MEP Struan Stevenson, with Mr Coburn elected for Ukip.
Mr Salmond said his party was on track to poll most votes north of the border and ''win yet another election''.
He told the BBC that the SNP's share of the vote so far was ''exactly where we were five years ago'', adding that from there his party went on to a landslide victory in the 2011 Holyrood elections.
The First Minister said: ''After seven years in government, it looks like we're going to win yet another election in Scotland. I don't think that's too bad a performance.''
He also contrasted Ukip's performance in Scotland to that party's stronger showing south of the border.
''It's a question of whether the SNP will get a third seat out of six or whether Ukip will get one seat and fourth place in Scottish politics,'' Mr Salmond said.
''That seems like a world of difference from the results I'm hearing in England, where Ukip seem to be topping the polls.
''I hope that we manage to keep Ukip out of Scotland. But there's a difference between a party getting perhaps under 10% of the vote in Scotland and over 30% in England.''
Scottish Labour deputy leader Anas Sarwar said: "We are pleased that our positive and energetic campaign, making the case for Scotland working in partnership with our neighbours across Europe, has made sure we have retained our two MEPs and increased our support.
"After knocking on thousands of doors over the last few weeks, speaking about the issues that matter, we have closed the gap on the SNP and moved ahead in some key areas.
"Right across Europe, nationalist parties are taking advantage of the economic downturn and with Alex Salmond fighting Nigel Farage for the last seat in this election, it is clear that this is no different in Scotland.
"It is time for the moderate majority of Scots to assert themselves, as we believe they will on September 18 in standing up to these dual forces."
Scottish Liberal Democrat leader Willie Rennie said it was "not a big surprise" that George Lyon had failed to be re-elected to the European Parliament, saying his party was continuing to "pay the price" for being in government with the Tories at Westminster.
Mr Rennie said: " George Lyon was an outstanding representative for Scotland in Europe and has been a huge credit to himself and the Liberal Democrats. Although his loss was not a big surprise, I am still desperately sad about his defeat.
"I do take some comfort from our stronger performance in seats with Liberal Democrat MPs and that our share of vote has risen since the Holyrood elections. But that is not enough - I am determined that we will do better.
"We continue to pay the price for being in coalition and for the decisions we have taken in government. I get that.
"In this election we put forward a positive case which was unashamedly pro-European. Despite our defeat, I am proud of that."
Even though the Greens failed to win their first Scottish MEP, the party hailed the European elections as their best result north of the border.
With almost all the results in, the Greens had picked up 8.1% of the vote, compared to 7.3% in the last European elections.
Lead Green candidate Maggie Chapman said: " In this election we asked 'What kind of Scotland do you want?'. The response has been the biggest-ever vote for the Greens, showing growing support for our vision of a Scotland which prizes economic justice, welcomes new Scots from around the world, and stands for peace.
"While I am personally disappointed at falling just short of election, I am also delighted that it looks like our sister party in England will increase its number of Green MEPs and that, across Europe, Green MEP numbers are rising.
"Like most Scots, I am troubled by far-right Ukip securing a foothold in Scotland despite no presence on the ground or interest in what happens here. Obviously millionaire backing and blanket media coverage counts for something. But, over the next five years, as people in Scotland see what a Ukip MEP looks like, I am confident they'll realise what a waste a Ukip vote is."
The Tories said their share of the vote was up, with a party spokesman stating: " The results tonight show the Scottish Conservatives are reconnecting with voters across Scotland, many of whom are voting for the first time.
"To increase our share of the vote in a six-party contest for the first time is further proof that the party is moving in the right direction and standing up for the issues that matter to people, such as giving them a say on Europe. This gives us a great platform for the general election and Ian Duncan will make a fantastic MEP for Scotland."
About 33% of people in Scotland voted in the European elections, the Electoral Reform Society said.
While this is up from the 28.6% turn-out north of the border in 2009, Willie Sullivan, director of the Electoral Reform Society in Scotland, said: " Voter turnout is low and declining in almost all public elections held in Scotland.
"The European elections are just an extreme case. Despite being higher than 2009, this particularly low turnout is perhaps because the public's reasons for ignoring the political system are amplified in the election of MEPs."