According to the latest poll from the Institute of Management, backing for the Tories is up from 40 per cent in the week before Easter to 43 per cent. Labour remains steady on 24 per cent, while the Liberal Democrat's polled 20 per cent - up three points.
More than half of those - 55 per cent - feared that Labour's proposals for statutory recognition of trade unions would increase the likelihood of industrial action. Seven in 10 managers said it was better to communicate with staff directly than through unions, although 87 per cent said employees should have the right to join a trade union.
However, the poll also contained some unwelcome news for the Conservatives. Their support among managers has dropped by 19 points since the last election and 49 per cent of those polled in the latest survey believed it was time for a change of government.
Just under half - 47 per cent - said the Tories had lost touch with the real needs of business, while 48 per cent said they did not believe a change of government would damage their business.
The Tories still scored better on the economy, with 60 per cent approving of their economic management compared with 43 per cent saying they would trust Labour to run the economy competently.
But there was concern among more than a third of managers that the current boom - the focus of the Conservatives election advertising campaign - would be followed by bust.
Despite the pick-up in Tory support, Margaret Beckett, Labour's trade and industry spokeswoman, seized on the poll, saying: "The business community has become increasingly concerned with the division and incompetence of the Conservatives and they have become increasingly interested in hearing the real truth about Labour's approach and policies. The Institute of Management survey shows that the more managers hear from us, the less they are taken in by the Tory propaganda machine."
Roger Young, the Institute's director-general, said: "Managers seem in a mood to change and will swing behind the party that is most in tune with the business agenda.
" Some discordant notes are sounding on the current consumer boom and a possible rise in inflation. Managers want to hear the right noises on the key issues of economic management."
The poll was conducted among Institute of Management members by Quick Reaction Survey during the last week. Of those contacted, 349 replied - a 49 per cent response rate.Reuse content