ComRes reported that 49% dismissed the suggestion he is a danger, compared to 24% who felt he was and 27% who did not know.
A series of questions about Ukip's appeal also found that 40% of the 1000 adults polled agreed that it is a party of the far right, compared to 38% who disagree.
The research also shows that support for the Conservative Party has dropped by 1% while Ukip's has increased by the same amount.
Labour are unchanged on 36%, the Tories are down to 30%, the Liberal Democrats are unchanged on 9%, Ukip are up to 12% and the other parties remain on 13%.
Meanwhile, the Tories have failed to capitalise on the Budget by falling three points since March in an ICM phone poll of 1,000 adults.The Coalition partner is down three points on 32% with Labour down one on 37%.