Survey of 26,000 voters suggests Tories would lose 83 MPs with swing of 6.5 per cent to Labour.
Sources say senior figures such as Harriet Harman, Ed Balls and Yvette Cooper were not given the chance to make high-profile interventions.
The party is on course for its best result in London since 1998 and has won in some key general election targets.
Cameron fears the collapse of the coalition. Labour fears a more popular centre-left leader.
The party needs large gains to demonstrate that it can win the general election and to compensate for possible defeat to Ukip in the Europeans.
Labour's preoccupation with policy too often resembles a displacement activity to avoid the thornier issues of leadership and economic competence.
The Labour leader won't U-turn if Ukip win the European elections.
A new poll shows the party trails in 25 must-win Conservative seats.
Labour leader will travel across five regions to promote ten "cost-of-living" pledges.
There are some sectors that could easily afford to pay workers more.