In another survey, manufacturers say by a large margin they trust the Tories most to introduce the best policies for them.
The snapshots will buoy up David Cameron and colleagues ahead of European and English local elections, although despite the figures, Ukip is still expected to be the biggest gainer later this month.
Last night, an ICM poll had Labour losing six points over the month to fall to 31%. The Tories rose one to 33%.Ed Miliband's party is at its lowest ebb since June 2010 after of Gordon Brown's General Election defeat.
The snapshot also showed Ukip rising four points to 15% and the Liberal Democrats up one to 13%.
The first of a series of weekly telephone polls for Tory peer Lord Ashcroft painted a similar picture, putting Mr Cameron's party on 34%, two points ahead of Labour, with Ukip third on 15% and the LibDems on 9%.
Around 40% of 1000 manufacturers questioned for the annual Engineered in Britain survey favoured Conservative policies. Only 5% backed Labour and 3% backed the LibDems. 28% said no political party had the right answers.