For the last 12 years, John Lamont has been campaigning to represent the Scottish constituency of Berwickshire, Roxburgh and Selkirk in the UK Parliament.

In 2015, the Conservative politician lost out on the seat by just 328 votes to Scottish National Party candidate Calum Kerr. This time around, he's is cautiously optimistic that things will be different.

"It's going to be close. It was close last time and I don't doubt it'll be close again."

Berwickshire, Roxburgh and Selkirk is one of several battleground constituencies for the Conservative Party next week's snap general election.

Prime Minister Theresa May called the election three years early in order to consolidate support for Brexit and, arguably, take advantage of historic levels of public support for the Tories.

Here in Scotland, however, the left-wing Scottish National Party holds the majority of seats in the Scottish Parliament and has led the country's devolved administration since 2007.

In the 2015 general election, the SNP was wildly successful in persuading voters that it was also the best choice to represent their concerns in the UK Parliament.

The party's share grew from just six seats in Westminster to a total of 56; a colossal victory that reduced the three unionist parties - Labour, Liberal Democrats and Conservatives - to just one seat each.

On June 8th, the SNP is widely expected to hold the majority of these seats. But polls now increasingly suggest that Scotland's election has become a two-horse race between the SNP and the Conservatives.

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So, how has the Conservative Party, which hasn't held more than a single UK Parliament constituency here for 16 years, positioned itself as such a strong contender?

The answer comes down to Scottish independence.

In both the recent Scottish independence and Brexit referendums, Scots voted resoundingly for the status quo.

But the looming prospect of a so-called 'hard Brexit' has led First Minister for Scotland Nicola Sturgeon and the SNP to call for a second referendum on the question of independence. She argues that Brexit is not what Scots signed up for when they voted to remain part of the UK in 2014.

But even since the Brexit vote, views on Scottish independence have barely changed, hovering around 45 percent in favour and 55 percent against. And fewer than half of Scots would like to see a second referendum on the issue.

An already strong Conservative Party in England is, therefore, hoping to benefit in Scotland from public opposition to another independence referendum.

Lamont, who has been a Member of Scottish Parliament since 2005, resigned in order to run for UK Parliament, calling the June vote "one of the most important general elections Scotland has ever had.'

He says the possibility of a second referendum is giving him a powerful campaigning message.

"Clearly, we have an issue in Scotland now where the Conservative Party is firmly in line with the views of a large chunk of the electorate," he told Al Jazeera.

"[Independence] is the main issue on the doorstep, and it's galvanised support for the Conservatives and polarised us against the SNP."

The matter is also encouraging tactical voting, with some voters willing to put aside traditional political allegiances in order to keep out the SNP and avoid a second referendum.

One constituent told Al Jazeera that she supported Lamont, but "if the Lib Dems had been the strongest voice in the constituency capable of defeating SNP, I would have voted for them."

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An hour's drive west is Dumfriesshire, Clydesdale and Tweeddale. Like Lamont's intended seat, it's a mostly rural community with contrasting pockets of affluence and deep, often hidden, poverty.

It's also one of just three seats in the country that the SNP didn't take when it almost completely swept the board last general election.

This time, the SNP's candidate will be 24-year-old trainee solicitor and party activist Mairi McAllan.

She doesn't agree that another referendum is the most important issue on people's minds here.

"What the Conservatives need is an issue behind which to hide their appalling record in [UK] government, but I don't think voters will be fooled," she says.

The partner of a sheep and cattle farmer, McAllan understands all too well this rural community's fears that Brexit could remove the UK from the single market, reducing farmers' ability to hire seasonal workers and ending their access to agricultural subsidies.

And in a constituency where one in five children lives below the poverty line, she says residents are also afraid of the effects of further cuts to local services.

"We're risking an emboldened Conservative government with an increased majority continuing their austerity cuts, particularly with their welfare reform package," warns McAllan.

Ultimately, the SNP has a hard task in advance of it in this election. Its massive success in 2015 means it has less to gain this time around, and far more to lose.

And while Nicola Sturgeon insists that an SNP victory on election night would "further reinforce" her party's mandate for a second referendum on independence, any Scottish seats that the Conservative Party can seize on its unionist platform may also allow Theresa May to more confidently justify refusing such a referendum.

On June 8th, how Scots cast their votes will once again, therefore, come down to the same questions of national identity that inspired two referendums in three years. And as with these previous attempts to reach a consensus, it's going to bring up more questions than it answers.

Candidates for Berwickshire, Roxburgh and Selkirk:

Caroline Burgess, Liberal Democrat

Ian Davidson, Labour

Calum Kerr, SNP

John Lamont, Conservative

Candidates for Dumfriesshire, Clydesdale and Tweeddale:

Douglas Beattie, Labour

John Ferry, Liberal Democrat

Màiri McAllan, SNP

David Mundell, Conservative

Source: Al Jazeera News