Nigel Farage on the Today programme quoted the British Election Study poll suggesting that in the general election Ukip will keep nearly 60 per cent of what it polls tomorrow in the Euro elections. I’m not sure even people involved in that finding really believe it.

Pollsters say individuals don’t like appearing fickle and ready to change their mind quickly and that the “retention” question is not a reliable one to predict outcomes – better simply to conduct a general election preference vote in the same poll and spot the difference. That said, the BES managed to predict Ukip’s vote retention pretty accurately from the 2009 Euros to the 2010 general election – they predicted 4 per cent Ukip share of the vote in 2010 and Ukip got 3 per cent.

Tory strategists are convinced that Ukip will come top tomorrow in the Euros despite some evidence of a slight slide in some polls, not least because more than 40 per cent of votes may have been cast in the post before the other parties and the  newspapers fully turned their fire on Ukip.

But Tories hope they can calm their troops down as the results come in on Sunday night by claiming that Ukip has peaked. Not least they’ll point at Nigel Farage’s declining rating as a leader. Tory strategists hope they can, with allies in the press, brutally focus on his inconsistencies in the months to come to batter him down further. One Tory strategist compares him to a “shock jock” radio host whose daily rants won’t measure up to what voters expect of a leader.

Not that Tories think he’s going to disappear. They are increasingly resigned to him retaining just under 10 per cent share of the vote. But they point out that in many marginal seats in 2010 the combined Ukip and BNP vote was around 10 pee cent anyway. The BNP vote has crumbled, mostly into Ukip’s hands. Things haven’t changed that much, is the argument. The margins aren’t so forbidding.

Tomorrow has long been in Tory strategists’ diaries like a pre-booked heart attack. The Euros would unleash Tory demons and lead to a carnival of political self-harm. The leadership now hopes it’s done enough work behind the scenes and got enough signs of Ukip-squeezing progress to point at to calm nerves and avoid serious division after the results.

Nigel Farage boldly said the Newark by-election will prove whether or not Ukip has peaked. If he comes second there two weeks from now, having just come first in a national poll, the Tories will say that’s exactly what he’s done. That by-election is now central to both parties’ strategies.

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