Is it true that voters are deserting the big political parties equally

The BBC keep pushing the idea that voters are deserting Labour and Conservative parties and lending their votes to the smaller parties - Greens & UKIP being the two usually mentioned.

Daniel Hannan reports the situation in his EU constituency is somewhat at variance to this:

"what my focus group is telling me is very different from what Westminster pundits are telling each other. You might think - I certainly thought when I started - that all the main parties would be suffering equally from the revelations in this newspaper's "Expenses Files". But they're not. Yes, some people will cast protest votes (overwhelmingly, in my patch, for UKIP or the Greens). A few say they won't vote at all - which, of course, is the most common response to Euro-elections, even in normal times. But huge numbers are switching directly from Labour to the Conservatives.

...

What do I conclude from all this? I'm sticking to my prediction, first made a week ago: the Conservatives will win big, Labour may well be pushed into fourth place - or even, in my patch, fifth place."

Interesting... I wonder why the BBC are pushing the idea that Tories and Labour will suffer equally?