David Cameron has urged potential Ukip voters to "come home" to the Conservatives on May 7.
The Prime Minister said the General Election was "not a time to send a message or make a protest" but to stop Ed Miliband and Labour forming a government.
Cameron said: "I would say to those people that I totally understand the frustration people have felt about issues like immigration where they want more done, and we will do more.
"And I understand the frustration about Europe - where the country deserves a referendum - and with me as Prime Minister they'll get that referendum.
"But this election is not a time to send a message or make a protest. This election is about choosing the government of our country for the next five years, and the choice could not be starker between a Conservative government led by me, continuing with a plan that's working, and putting it all at risk."
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