David Cameron should form a non-aggression pact with the United Kingdom Independence Party at the next general election amid fears the anti-EU party could cost them up to 30 seats, according to a majority of Tory grass roots activists.
A survey conducted by the Conservative Home website showed that 60% of those asked thought the prime minister should strike a deal that would stop Tory and Ukip candidates standing against each other in marginal seats.
Ukip has enjoyed a surge in the polls and according to polling firm YouGov as many as 1.4 million people who voted Conservative two years ago have transferred their allegiance to UKIP.
Ukip has enjoyed an increase in support and in April the party out-polled the Liberal Democrats nationally for the first time, jumping to 9% compared to the Lib Dem's 8%.
Peter Kellner, the president of YouGov, has said he would "not bet heavily against" Ukip topping the poll in 2014 European elections.
Kellner said in April that while Ukip might not be able to secure enough votes at the 2015 general election to get its first MP, it could do well enough to scupper the Tories.
"Suppose it wins over just 2,000-3,000 unhappy Tories in each of the key marginals," he said.
"This kind of division on the Right would be enough to cost Cameron up to thirty seats, and hand victory to Ed Miliband. If the shift to Ukip is much greater, Labour could win by a landslide."
Last week Ukip leader Nigel Farage said the Conservatives were now "virtually indistinguishable" from Labour and the Lib Dems on many big issues.
"We are not voting to change governments in Britain. We are voting for a change of management," he said.
However Farage told The Times that his party would “certainly consider” an offer of an electoral pact with the Conservatives.
“It is obvious that Cameron’s voters and members are more closely attuned to Ukip than they are to either Cameron himself, or the Liberal Democrats," he said.
Relations between the Tories and Ukip have not been that cordial in recent months, with a Ukip spokesman to branding the Conservative Party chairman Baroness Warsi "a bitch" after she appeared to link the anti-EU party with the far-right BNP.
Dissatisfaction with Cameron's approach to the EU was highlighted last year when 80 Tory MPs defied the government to vote in favour of a Commons motion calling for a referendum on Britain's membership.
Conservative peer Lord Vinson recently warned that he would be prepared to defect to Ukip unless the prime minister adopted a more eurosceptic tone.
“I and many others will leave the Conservative party unless we get a clear signal from Cameron because our relationship with Europe is extremely damaging and we would be better off out," he said.
The least popular idea in the survey conducted by ConHome was that the Tories enter into a pact with their current coalition partners.
Of those asked 55% thought a pact with the Lib Dems would have a negative in impact on the Tories chances of winning the net election.