While it seems clear that SNP support in the EU elections will dip a bit due to a small protest vote by some supporters this seems unlikely to have any longer-term effect on Westminster voting intentions. The Opinium sub-poll for 8th May gives
- Con 22%
- Lab 12%
- Lib 7%
- UKIP 4%
- SNP 41%
- Green 2%
- Chuka 1%
- Brexit 13%
Though this suggest a fall from the around 45% figure being recorded in the months before the launch of the Brexit Party, 41% was the steady figure poll after poll before that and, of course, will be enough for an almost complete wipe-out of the other parties. Interestingly, Flavible Politics used the above data to predict 53 SNP and maybe 3 Lib Dems. Do the strong winds in the Northern Isles blow away the stench of Carmichael?
For the European election the results we get are:
- Con 14%
- Lab 11%
- Lib 8%
- UKIP 4%
- SNP 40%
- Green 5%
- Chuka 1%
- Brexit 16%
So, the hit caused by Brexit looks like being taken by the Tories and Labour. Flavible read this to mean the SNP would take 3 of the 6 EU seats with 1 each for Lab, Con and Brex.
https://www.opinium.co.uk/political-polling-8th-may-2019/
Talking-up Scotland 
As a very small point of detail, I am not sure your conclusion is quite correct. Last time round the SNP won two seats, the Tories one, as well as that UKIP idiot who thankfully is not standing again for anyone.
However, Labour won two – David Martin and Catherine Stihler. So the “hit” looks to me as if its on Labour, which as you say, would on the evidence of this poll win only a single seat, while the Tories retain their single seat and a Eurosceptic party – though the Nigel fan club rather than UKIP – would retain their seat.
So its really Labour lose one to the SNP.
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Thanks for the correction. I fly solo here and too fast sometimes to check. Will edit it.
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