Because most right centre or right wing people prefer to keep their opinions to themselves rather than have an argument over their voting intention. Whereas most left centre or left wing people don't suffer the same response.
Hence why violent "left wing" groups get a free pass and virtually no reporting whereas non violent right wing groups like EDL will be headline toppers despite no violence on their side and all the arrests being from the "anti" lot.
When it is fine to shout Tory scum yet the left wing are immune from criticism then you will not get the same numbers airing their views.
The whole of the internet shows this. You would think 90% of voters were left wing if you gauged opinion on the internet. Or you would get the impression that right wing people don't use the internet. The reality is that most right wing people on the internet just can't be bothered having the same old argument and getting the same aggressive response whereas the left wing posters post away because they don't receive the same response because of the above.
Polling day will tell. YouGov will have overestimated the left wing support again and they will never get to grips with the "shy" right wing vote because there are more and more "shy" voters as the days and months progress due to the increasing vitriol from the left.
YouGov had Ed Milliband closing the gap and towards polling day Milliband was neck and neck with Cameron with YouGov still thinking it was going to be a coalition by a margin with The Labour not being too far behind Cameron in terms of seats. The reality of course was a difference of 99 seats.
This is YouGov's opinion 6th May 2015 in the Guardian:
Now, with only a few days remaining, Ed Miliband and David Cameron are still squaring up against one another and although a knockout blow now looks virtually impossible, there are still points to be won and the result remains very uncertain.
Miliband has adopted an aggressive, confrontational stance by ruling out any kind of coalition or deal or agreement or whatever with the SNP. This will, one imagines, result in him being left well short of a majority and having to go all Michael Corleone – offering the SNP nothing, but hoping they blink first and fall in line as their opposition to the alternative is too great.
However, David Cameron may keep fighting and refuse to give in. Crucially, he will need to, as I expect, win slightly more votes and a few more seats than Labour, but also convince the remaining Lib Dems to enter into a formal coalition agreement. No easy task, but by no means impossible.
If he succeeds, we could be left with both Con/LibDem and Lab/SNP blocs close in terms of seats although still short of the 326 (or even 323) needed for a majority, but with the Conservatives able to claim a points victory by virtue of being the single party having more votes and seats.
All the pollsters went for a neck and neck hung parliament or Ed Milliband for PM. NONE predicted Cameron except "Populus" who were working 3 days a week for the Conservatives at the time.
Michelle Harrison, global head of public affairs at TNS: ‘Stalemate; Miliband has the numbers, but public opinion will decide’
Survation's opinion from their polling in May 2015, how far out is this one? And that is with Labour ahead in the polls not just neck and neck!!!:
Our new ballot paper-prompted voting question, which we believe will produce results closer to the actual results tomorrow, currently shows:
CON 31.0% LAB 32.3% LD 10.1% UKIP 15.2% GRE 5.4% SNP 3.9% Others 1.8%.
This would indicate a seat picture of:
CON 270-280 LAB 270-275 SNP 45 LD 30 UKIP 6 GRE 1 RES 1.
Ed Miliband would then, on this basis be our most likely next prime minister, and LAB could be closer to the Conservatives in both votes and seats than is the current expectation – lending some “legitimacy” to the formation of a Labour minority government.
These pollsters will never be able to work out the shy vote because they don't understand of realise how much vitriol there is that is pushing people to be "shy." That vitriol is increasing and thus the "shy" vote will increase with it.
