Do you feel lucky?
The polls have closed. The count is underway.
First and best info, of course, here on the BBC.
First, a little background. Labour comes to this Scottish Westminster by-election - on the back of two catastrophic defeats in England.
They lost Crewe and Nantwich - with a 17% swing to the Tories.
And they came an embarrassing fifth in Henley.
But this is Glasgow East. Where they normally weigh the Labour vote.
In various guises, it's been Labour since 1922. Since the Labour movement started winning at all, they've won the east end of Glasgow.
To win tonight, the SNP needs to record a voting swing from Labour of just under 22%.
That's huge - but they've done it before. Winnie Ewing took Hamilton in 1967 with a swing of nearly 38%.
That's artificial, though. The SNP was starting from zero - because the party didn't fight the seat in 1966.
But in 1973, Margo Macdonald recorded a swing of nearly 27% to oust Labour.
Then in 1988, Jim Sillars - now Margo's husband - took Govan for the SNP with a massive swing from Labour of 33%.
Scotland, he declared, was on the march.
Those are the famous SNP victories from Labour. Repeat that level of performance tonight - and the SNP will win.
But. More commonly, the SNP has forecast victory - and even recorded a good showing - only to fall short in contests with Labour.
In 1978, Donald Dewar held off a Nationalist challenge to win Glasgow Garscadden.
The same year, George Robertson entered the Commons by defeating the SNP in the iconic seat of Hamilton.
In 1989, a year after Jim Sillars' Govan triumph, Alex Neil registered a 15 point swing from Labour in Glasgow Central. But it wasn't enough to win.
There were two by-elections in Paisley in November 1990. Two strong SNP performances. Two seats held by Labour.
In 1994, Monklands East - perhaps the most bitterly fought by-election in Scotland. A swing to the SNP of nearly 20% - but Helen Liddell held the seat for Labour.
Paisley South, November 1997, decent swing to the SNP - but Douglas Alexander won for Labour.
1999 - and it's Hamilton again. Hamilton South. A swing of more than 22% to the Nationalists.
Not enough on the night - although it would do this evening for the SNP.
Glasgow Anniesland in 2000 after Donald Dewar died. Falkirk West in 2000. Livingston in 2005. All Westminster seats with a strong SNP challenge. All held by Labour.
So the question tonight for the SNP is not: Do you feel lucky? The question should be: Is this Govan or Garscadden? Hamilton '67 or Hamilton '99?
Further update..... So a recount then. Despite the absence of an outcome, thought I'd post a little blog to keep the pot boiling.
Consider the environment here - Labour's third safest seat in Scotland - that is untill tonight. If the SNP do win, as seems likely, they will have pulled off a stunning result against their rivals.
Of course, we must await the final outcome but it would seem evident that the people of the East End of Glasgow have turned against Labour.
Or, more precisely, that their disquiet, discontent and indeed anger at their circumstances have combined to produce a poor result for the party which has held this seat since whenever.
The scunner factor has been well to the fore.
Again, we must await the final outcome. However, I believe that Labour would make a mistake if they were to attempt to blame Gordon Brown solely for their poor performance.
I confess I have only spent a few days in the constituency but my impression, borne out by others, is that folk are fed up with what they are currently hearing and receiving from Labour, not just its party leader.
For the SNP, further proof that they can turn out a vote in areas which were previously sceptical, if not hostile. It is a further tribute to their increasingly impressive electoral machine.
More later...... when we have the result.