Sixty per cent believe immigration has benefited Britain and are much more likely to be pro-EU.
The Newark by-election saw centre-left voters hold their noses and back the Tories to stop Ukip.
The party holds the seat with a majority of more than 7,000 as the Lib Dems are pushed into sixth place.
The party is still achieving record ratings in the national polls.
Lord Ashcroft's poll puts them 15 points ahead of Ukip, but they trail Labour by nine points nationally.
Roger Helmer, Ukip's Newark by-election candidate, has responded to the Mail's story about him supporting "gay cures" on the NHS. Angrily.
Ukip leader says "For half the country it benefited them, for the other half it didn't."
The party should face a far more rigorous examination of its unscientific beliefs.
With a week to go, the party's eight-point lead is too small for comfort.
Anti-Semitism is now taboo in mainstream political discourse in a way in which Islamophobia isn’t.