in a direct appeal to voters who have shifted allegiance to nigel farage 's party , the prime minister vowed to ` do more ' to respond to concerns about immigration .
with the election on a knife-edge , he warned that it is ` not the time to send a message or make a protest ' that he understood the ` frustrations ' of ukip voters .
it is a significant peace offering by the prime minister , who once dismissed ukip as ` fruitcakes , loonies and closet racists ' a steady squeeze in support for ukip that