The UK Independence Party's leader says he has overwhelming backing from local chairmen after conducting a phone poll.
Mr Kilroy-Silk says the party is not grown-up
He says Robert Kilroy-Silk must stop his attacks or perhaps leave the party.
The party asked 162 branch chairmen who they would support in a leadership vote - current leader Roger Knapman or ex-TV host Mr Kilroy-Silk.
Its says more than half wanted Mr Knapman and just 25 supported Mr Kilroy-Silk, who has dismissed the poll as a "banana republic" style exercise.
After some confusion over the figures, UKIP said 109 branch chairmen had backed Mr Knapman's leadership, 25 had said they supported Mr Kilroy-Silk and 28 were undecided.
The party is still trying to contact the remaining 62 branch chairmen before announcing the final result.
Mr Knapman said the question over his leadership was now settled.
Senior party figures will be writing to Mr Kilroy-Silk to demand he stops attacking the party.
Mr Knapman told BBC Radio 4's Today programme: "We are asking him to make up his mind either to support the party or plough a single furrow."
Asked about reports that the MEP could lose the UKIP whip at the European Parliament, Mr Knapman said that point had not yet been reached.
It was hoped Mr Kilroy-Silk would now be a good team player, he said.
"If he can't be a good team player, he owes it to himself and the party to consider his future carefully," added Mr Knapman.
Mr Kilroy Silk told the BBC he would be carrying on his campaign to give the party "proper leadership".
He poured scorn on the poll and likened the party to a "pressure group run by a cabal".
The survey was carried out after Mr Kilroy-Silk wrote to the branch chairmen calling for an open leadership contest.
It comes as the ex-chat show host is due to make a speech in the Wokingham constituency of arch-Eurosceptic and Tory MP John Redwood, where his comments are likely to be closely monitored.
Kent businessman and UKIP donor Alan Bown has rejected the call for a leadership contest.
Mr Bown, who has promised to fill any funding gap left after UKIP's biggest donor, Paul Sykes, decided not to finance its general election campaign, said: "It seems to me completely unnecessary to go through a leadership contest so near to a general election.
"The figures agree with my own view that there should be no contest.
"Consequently, I am appealing to Robert to abandon his leadership bid for the sake of party unity."
Speaking after the initial results of the telephone canvassing, he said: "If Robert decides to continue with his leadership challenge, I will reluctantly have to reconsider the funding that I have promised for his personal election campaign in the East Midlands.
"But of course, I will continue to be a strong financial supporter of UKIP nationally."
Later, Mr Kilroy-Silk told BBC News Online: "I am not for sale and never have been.
"I decide what is right politically on the basis of my principles and my beliefs and not on the basis of who is waving the biggest chequebook in my face."
He said the telephone survey was a panic measure.