Well I suppose hating immigrants is now "mainstream" now
Virtually every trend in public opinion shows that positive sentiment toward immigrants is at or near an all-time high.
I would argue that wording is a loaded question of sorts. I don't think many anti-inmigration people deny that inmigrants on the whole (or at least certain subsections) do work hard, strengthen the country and what not
A more interesting question would be "Would you like inmigration to increase, decrease or stay at current levels?"