Well for a number of reasons. There's a host of British attitude surveys which suggest that's the case, it's very obviously vastly less racist than when you could openly discriminate against someone due to their skin colour (no Irish, no blacks etc), all people are happier for a member of their family to marry someone with different colour skin than even ten years ago, there seems to be a greater number of successful black people in the UK than ever before. I read a stat the other day that higher percentages of black people now go to university than white males (I'd have to find where I read that though). I think one of the downsides of some campaigns is that it seeks to divide people on racial lines rather than focusing on what we all have in common as UK citizens.