If consensus opinion it to be believed, then the European Parliamentary Elections here in the UK will deliver a clear victory for Nigel Farage and the Brexit Party, while the traditional ‘main parties’ of British politics get something of a hiding – particularly so the Conservatives. The Liberal Democrats and Greens seem set for very positive outcomes, while UKIP – just as the BNP before them – will be wiped off the map by a new anti-EU, populist-right party. Change UK are expected to struggle to secure even one MEP, while Labour could even be squeezed into third by their staunchly-Remain Liberal Democrat opponents, and are already wheeling out an expectation game to match.

Flash back to 2014, and the Conservatives were finishing in third, behind a Labour Party in full belief of its ‘government in waiting’ position and an insurgent UKIP, very much headed toward the peak of their powers and influence. The Lib Dems were well down the line on their slide into electoral oblivion (which would bottom out at the General Election the next year), while the Greens were in the middle of what they dubbed the ‘Green Surge’, picking up in that year thousands of new members, gaining an extra 18 councillors at the locals, and winning a new European Parliamentary seat (taking their total to three).

That 2014 result was broadly in line with what was expected from the polling, but with the Conservatives ultimately doing a little better (in terms of vote share) and Labour, the Lib Dems, and UKIP slightly worse.

Let’s imagine though that the central set of expectations for the results tonight are misguided. Instead of a solid victory and a hatful of seats for Farage, decimation for the Conservatives, and the Liberal Democrats and Greens marching right up close to the traditional ‘top two’, what if a very different set of outcomes – but one completely possible with the range of opinion polling – comes to pass? What kind of election result would we be looking at?

Looking at the polls over the past couple of weeks (nod to Professor Will Jennings here), the range of possible vote shares for both Labour and the Brexit Party are enormously wide. Across all British Polling Council registered pollsters, the spread of possibilities is comprehensive to say the least.

For instance, Nigel Farage’s group could be anywhere from nearly 40% down to a little over a quarter of the overall share. Which is exactly where the high-end of the Labour Party’s expectations, according to the polls. Corbyn’s party could conceivable sit at anywhere between 13% and 25%, meaning – potentially, but rather unlikely – that we might even see a battle for 1st place emerging over Sunday night.

Party Minimum Share Forecast (POLITICO) Maximum Share
Brexit Party 27% 32.90% 38%
Labour Party 13% 19.10% 25%
Liberal Democrats 11% 16.00% 20%
Conservatives 7% 11.10% 15%
Greens 4% 8.60% 12%
Change UK 3% 3.80% 5%
UKIP 2% 2.80% 5%

Polling data comes from May entries in the Wikipedia archive of 2019 European Election voting intention polls for the UK. Central forecast courtesy of POLITICO.

If the Brexit Party did end up somewhere are the bottom end of their polling, this would be a pretty-much identical result to that which UKIP achieved in 2014. Back then, 26.6% was enough to win the party 24 seats across the 11 British regions. Similarly, a result at the top end of Labour’s polling would again be very close to their 2014 result, where 24.5% of the popular vote put Ed Miliband comfortably in second place, picking up 20 seats.

So even looking at the current polls, a result between the top two parties which closely matches what we saw in 2014 is very much a possibility. Is there any reason to think this might happen? Well, concerns have already been expressed regarding the potential of (particularly online polls) to be flooded with hyper-engaged, hyper-mobilised Leave voters filling up panel quotas – something which happened previously with UKIP. So yes, Brexit Party support could on average be very much overestimated. As well, in the last nation-wide ballot – the 2017 General Election – the average very much underestimated Labour’s voting intention. So yes, Labour could still be systematically lower in the polling average than they ought to be.

Moving on now to the other parties and their potential outcomes, the Conservatives in 2014 won 23.1% of the vote, coming in just behind Labour. Certainly the current polling puts them on average well down on that result (11% according to the POLITICO forecast), and indeed in very real danger of being pushed into fifth place by the Greens.

However, let’s continue to imagine a scenario where the 2014 baseline is a much stronger predictor of 2019 performance than currently assumed, and the Conservatives do end up toward the top end of their vote share – 15%. Perhaps it won’t all be as bad is as feared for the governing party, and that less voters than expected flocked to Farage’s outfit? 15% was enough to win Gordon Brown 13 seats in 2004, so the Conservatives may well be able to pick up the same amount with around one in 7 voters supporting them this time around.

Then, combined with the above, the pattern between the top three would look incredibly similar to how it did five years ago – Brexit/UKIP at the top and a couple points ahead of Labour in second, with the Conservatives again a little behind them (though with the gap down to third a little larger than last time).

And what about the Liberal Democrats and Greens, who both look to be very much up on 2014 according to central forecasts of current polls, with a strong chance (certainly in the case of the former) of overtaking the Conservatives?

Much has been made of the reported turnout change across almost 150 councils which have declared such figures ahead of the count this evening. Turnout is most definitely up in more Remain-inclined council areas, but there are three important notes of caution to be made about jumping to conclusion that this turnout pattern is going to deliver the most Remain-supporting parties a solid result.

As outlined in my recent blog post with Professor Sir John Curtice, Professor Stephen Fisher, and Eilidh Macfarlane (the BBC psephology team for tonight’s show), (1) a good amount of the effect is also down to whether or not local elections were held in the authorities in 2014 and/or 2019, (2) problems of endogeneity mean that we can’t be sure if these are Remain voters or Leave voters turning out in greater numbers – the Remain vote could already be ‘baked in’ to the baseline turnout figures and instead the increase could be otherwise not-inclined-Leavers coming out to protest, and additionally (to the points made in the blog) (3) thinking in terms of the above scenario, what if those additional voters (to the 2014 baseline) are traditional supporters of the ‘main two’ parties ‘riding to their aid’ after seeing the state of the polling, having not usually engaged in European Election voting before?

Therefore, there is still a possibility that both the Liberal Democrats may not benefit in particular and to the expected extent from a big anti-Brexit voting surge. Evidence does strongly suggest at least some advances for both, so let’s say that these two parties end up somewhere in the at the lower-middle of their current expectations, settling in at 4th and 5th with around 14% and 8% of the vote respectively (switching places from 2014). A 13% vote share in 2009 gathered in 11 seats for Nick Clegg’s Liberal Democrats, so perhaps an additional percentage point could see Cable’s party continue their recovery and go one better than Clegg did in 2009. Meanwhile, if the Greens were to also end up adding one percent to their 2014 total, they may well add just one additional seat from 2014 (moving up to four from three). For argument’s sake, let’s assume the same of Change UK (median forecast of around 4% of the vote and one MEP).

Again, how probable is all of that? Well the same arguments regarding the over-engagement of Brexit supporters could be levied at supporters of Britain’s most overtly Remain parties, and perhaps the moves in the week leading up to the European Elections by Labour Party heavyweights to ‘talk up the possibility’ of supporting a second referendum in parliament may have been effective in stemming the leakage of anti-Brexit Labour supporters away to the Liberal Democrats, Greens, and Change UK.

Taken together, with adjustments made for the likely impact of higher-performing Liberal Democrats and Greens on the eventual D’Hont seat distributions for the top three, it is well within the realms of possibility according to the polling that we end up with results reflecting something along the lines of the below. The figures are naturally very rough (no modelling done at all within regions), but give some guide as to the potential outcome under the above scenario.

Party Potential Share Approximate Seats
Brexit Party 27% 21
Labour Party 25% 19
Conservatives 15% 13
Liberal Democrats 14% 12
Greens 8% 4
Change UK 4% 1
UKIP 3% 0

Potential share and seats may not round and exclude three a piece for Northern Ireland. Seat wins approximated by comparing similar vote shares and minor party aggregate support to previous seat distributions at the national level.

So in summary, after all this talk of Farage and the Brexit Party romping home to a decisive victory, and an anti-Brexit voter turnout surge pushing Labour into 3rd and the Conservatives into 5th, in fact a picture very similar to 2014 may well still emerge. With, of course, the addition of the Brexit Party (who it should be said would have every right to be happy with winning the first election they ever competed) replacing UKIP at the top and the Liberal Democrats recovering to something like their 2009 form. How likely? Not very, but certainly possible. But if it does happen, at least after reading this you can say you saw it coming.