We all know the feeling.

You're walking down the street and somehow you get the sense that you have been here before. Like a half remembered dream.

It's that strange feeling of deja vu and it's because this General Election has turned into a re-run of last year's referendum campaign. It's uncanny. Even the weather's the same.

Yessers and Nawers have been scrapping with each other again on Twitter. The Better Together alliance has come out of temporary retirement to promote Project Fear II.

We've roughly at the stage where a couple of opinion polls puts the Westminster political establishment and media into a state of blind panic.

Daily Record subs are laying out the "Deja Vow" front page. It can only be a matter of time before Gordon Brown is trundled out again like Mons Meg for one last blast at the Nats.

This was always going to be an acrimonious election as Labour sought to halt the SNP advance and the Tories tried to monster Ed Miliband. But no one expected it would be quite like this.

I'm not going to repeat all the abusive remarks made about Nicola Sturgeon by Tory politicians and their pals in the press because it only encourages them. But over the top doesn't come close. There shall be a "communist dictatorship" according to Michael Gove's wife, Sarah Vine.

It's becoming almost impossible to satirise this election. It is self-ridiculing when Sir John Major, one of the least memorable Tory prime ministers of the past century, is wheeled out to claim that "merry hell" will happen if the SNP ever participate in the formation of a UK government.

Actually, merry hell sounds quite fun - a lot of people would vote for that. The SNP should put it on a leaflet.

Having discovered that Mr Miliband wasn't the pushover they expected, the Tories have decided to place the Scottish menace at the centre of their campaign. They hope that they can demonise the Labour leader by proxy through attacking Ms Sturgeon as the most dangerous woman in Britain "holding England to ransom" .

But when the ardent Thatcherite former Scottish Secretary, Michael Forsyth, has to call on David Cameron to button it, you know something weird is happening. When Norman Tebbit adds his voice you wonder if the men in white coats are going to arrive.

What Scotland needs, said the former Tory chairman, is "a Scottish-rooted genuine Unionist party like the Ulster Unionists". God help us. The importation of Northern Ireland sectarian politics is the last thing Scotland needs.

"But no one lost an election by spreading fear" according to Professor Vernon Bogdanor on BBC Radio yesterday. "Negative politics always wins because psychologists tell us we fear losing what we have".

Mind you, the Tories tested this theory to destruction in the 1990s, warning about the dangers and deficits of devolution. They lost all their MPs in Scotland by 1997. Now they're trying to do the same thing to Labour by urging their folk to vote for them.

Sir Malcolm Rifkind, no less, has advised Tories in Gordon to "think seriously" about voting Labour. Some Labour MPs have been putting out leaflets urging Tory and Liberal Democrats to lend them their support, which will do wonders for Labour's core vote.

Clearly, Labour needs to do something to combat Ms Sturgeon but this isn't it. Reconstituting the Better Together alliance may look good on paper; after all, the No vote won the referendum. As practical politics, it is highly doubtful. This isn't a referendum but a general election and the dynamics are very different.

Bedrock Tory voters will be hard pushed to believe that voting for "Red Ed" is better than the SNP, who've been holding down council tax and helping small business.

And how many Labour voters would really vote for the nasty Tories and austerity rather than nice social democratic Nicola Sturgeon?

Labour would be best advised to stop pretending this is the referendum because voters aren't stupid. They know perfectly well that they are not voting about independence on May 7. Come to that, they realise this is not a vote about Full Fiscal Autonomy (FFA) either. It could only happen if the Westminster parties voted for it, and they aren't going to.

The danger for Labour of any dalliance with tactical voting is that it brackets them with the hysterical Tory tendency of Messrs Major, Cameron and Tebbit. That is not a comfortable place to be.

Their complaint that Scotland is "holding England to ransom" is offensive and absurd. At best the SNP might have 50 seats out of 650 and the Scottish economy, as the Institute for Fiscal Studies (IFS) never tires of reminding us, is so enfeebled it couldn't cause any harm to anyone.

The IFS has been pressed into service by Better Together redux to make full fiscal autonomy look as ruinous as independence. In fact, it has largely used the same numbers as in the referendum spoilers, deflated for the oil price.

Scotland's deficit will fall from eight per cent to four per cent of GDP by 2020, says the IFS. But don't let that fool you. The "deficit" will still balloon to nearly £10 billion. How so? The argument appears to be that Scotland will be trying to play catch-up against the rest of the UK, which will be growing fast.

The essential problem with this analysis, as this column has also been arguing for weeks, is that it assumes the Barnett Formula is going to continue and that Scotland will forever receive its bounty. It is not.

Under the Smith package, it will apply to a much smaller proportion of Scottish spending. The rest will come from direct and assigned taxation. Interestingly, both the SNP and Labour are pretending, for different reasons, that Barnett will still be around in the background.

But this is all too complicated for an election in which facts are melted down and turned into bullet points. On the one hand, Labour is determined to play on the risks of independence or FFA. On the other, the SNP keep saying that Scotland is just as capable of running its own affairs as any other independent country.

That is a proposition with which it is very hard to argue, unless you assume some genetic incapacity in Scots, which some commentators seem to believe is the case. The articles pile up saying that Scots are mad, dim, ignorant and so on to contemplate voting SNP.

But the Scottish voters seem to be getting madder by the week. Ms Sturgeon's stratospheric personal popularity ratings are, according to the Labour blogger Dan Hodges, "insane". Only he means it. There is blank incomprehension in the metropolitan media at the electoral behaviour of the Scots. They cannot be serious!

We'll soon see whether Project Fear II is getting off the ground. The Unionist parties are eagerly expecting a dip in the polls this week as the voters tire of the SNP's pie-in-the-sky economics and start behaving sensibly again. Well, we'll see.

This has turned into an independence election, even though independence isn't on the agenda, and has been dominated by arguments over full fiscal autonomy, which isn't going to happen. In fact, you could say that in Scotland, at least, this election is a row about nothing.