Video report by ITV News Scotland Correspondent Peter Smith
Scotland is going to be fascinating in this election.
There are so many marginal seats, around half have a majority of less than 2,000. A quarter have a majority of less than 1,000.
In one seat - North East Fife - the difference comes down to just two votes.
Scottish voters are also being asked to chew over two meaty constitutional issues: Brexit, which doesn’t really cut through Scotland the way it does in England, given all constituencies voted Remain; and the real political divide of whether to stay in or leave the UK.
The two are linked.
Scotland voted just five years ago to stay in the UK, but did not vote to leave the EU. The circumstances have changed and people are thinking hard about whether being in the EU as an independent nation is now a better option than keeping Scotland in the UK.
For Nicola Sturgeon, this election is a kind of referendum on having a referendum. If the SNP dominates, she’ll say it’s proof Scotland is ready for another independence vote.
As the recognised leader of Scotland’s independence movement, she's quite comfortable with taking voters into that territory.
Scotland’s Unionists, on the other hand, go into this election still searching for the person who will be the de facto champion of their cause.
In the last election, Ruth Davidson led the charge, and the SNP lost more than a third of their seats. That forced Nicola Sturgeon to put the brakes on IndyRef2 in 2017.
But Davidson’s now resigned, and it's back on the table. The problem is those who would inherit her throne are struggling with something of an image problem.
A completely unscientific sample in a Glasgow hairdressers, few recognised any of the leaders of Scotland's unionist parties. None knew what their key message was about. Everyone, however, knew Nicola Sturgeon.
Jackson Carlaw is Ruth Davidson’s successor in the Scottish Tories.
He's focusing on the anti-independence message, but there is noticeably not a lot of Boris Johnson - or "get Brexit done" - on the Tory leaflets in Scotland.
Then there's Scottish Labour - now squeezed into third place here, battling to make themselves the party of the Union, in spite of mixed messages from the UK Labour Party.
Their leader, Richard Leonard, says they will absolutely not do any electoral pacts with the SNP to get Jeremy Corbyn into Downing Street.
The Scottish Lib Dems are against an independence referendum, but are accused of hypocrisy given they support a second referendum on Brexit.
The challenge for those who want to champion Scottish Unionism is to prove themselves against a dominant Nicola Sturgeon.
Because in Scotland, this election isn’t about Brexit - it’s a test ground for a constitutional battle that’s still to come, that could determine the very existence of the United Kingdom.