Nigel Farage's personal approval rating has slipped markedly in a new poll that puts the Ukip leader's popularity below David Cameron.
His net approval rating - the percentage of voters who approve of his performance minus those who disapprove - fell to -17%, eight points lower than a fortnight ago.
The Prime Minister was on -11%, with Ed Miliband on -28% and Nick Clegg on -48%.
Since the last Opinium poll Mr Farage has faced criticism for comments about breastfeeding in which he suggested that mothers could "sit in the corner" in restaurants while feeding babies to avoid offending people.
The party has also been hit by the resignation of would-be MP Kerry Smith over a leaked recording of him making derogatory comments.
The Opinium poll for the Observer also had bad news for the Liberal Democrats, who slipped to just 6% support, compared to 16% for Ukip.
The survey put Labour on 36% support, seven points ahead of the Conservatives.
Ukip members have been urged to avoid using social media following a series of controversies over inappropriate comments.
Party chairman Steve Crowther said his approach to sites such as Twitter and Facebook was "just don't" as the party updated its rules about use of its logo on the internet.
Ukip members and supporters have been involved in several rows over their online activity, but Nigel Farage's party has also been the target of spoof accounts using its logo.
A copy of the party's new constitution, seen by the Observer, lays out "rules for online communication", stating that:
Party members shall refrain from using the Ukip logo in terms of their online postings, including avatars, unless they have express written consent to do so from the party leader, the party chairman, the party secretary, the general secretary, the party director, the regional chairman or regional organiser for their region.
UKIP leader Nigel Farage has been criticised after his attempts to defend a former UKIP parliamentary candidate's remarks about Chinese people and homosexuals only appeared to make matters worse.
Mr Farage said controversial comments made by disgraced former Ukip candidate Kerry Smith were because he was a "rough diamond".
ITV News' Political Correspondent Carl Dinnen reports on how the controversy is affecting Mr Farage's popularity.
Winston McKenzie has lost his title as Lambeth and North Croydon chairman during an investigation which has seen the whole branch suspended.Read the full story ›
Nigel Farage has suggested a former Ukip candidate used the terms "chinky" and "poofters" because of his "council estate background".Read the full story ›
Kerry Smith has resigned as Ukip's prospective parliamentary candidate for South Basildon and East Thurrock after apologising for making offensive comments, he announced in a statement.
Recordings of phone calls obtained by the Mail on Sunday captured the would-be MP calling gay party members "poofters" and referring to someone as a "Chinky bird".
The comments were revealed just days after he was reinstated as the party's candidate in the top target seat - and Smith had already made an apology for deciding to resign.
I have this evening offered my resignation as Ukip PPC for South Basildon and East Thurrock.
I want the best for South Basildon and East Thurrock and I want to see the real issues discussed that touch the lives of people.
Therefore I have chosen to resign so that Ukip can win this seat next May.
A Ukip candidate has apologised after he was recorded making a series of offensive remarks about gay people.Read the full story ›
Ukip's general election war chest has been boosted by a reported £300,000 donation pledge from newspaper proprietor Richard Desmond.
Mr Desmond is believed to have discussed the gift at a meeting with the Ukip leader earlier this month. Sky News said it was not clear whether the money had yet been handed over.
We do not discuss donations.
If we receive them we report them to the Electoral Commission in accordance with legislation.
The Daily Express and Sunday Express have been strongly supportive of Ukip's stance on immigration and Europe.
Brand said 'we have to watch him' as he compared Farage to the Conservative politician best known for his 1968 "rivers of blood" speech.Read the full story ›