Trouble in the Tory ranks: Supporters less likely to vote.

Labour soars in polls as Tory voters grow less likely to vote

Labour soars in polls as Tory voters grow less likely to vote

Labour is enjoying its strongest polling since Gordon Brown's honeymoon, as a new survey shows Conservative voters are growing less likely to vote at the next election.

The latest monthly poll from Ipsos Mori puts Labour up four on 44%, the Conservatives unchanged on 31% and the Liberal Democrats up two on 12%.

The strength of the 13-point Labour lead is partly due to Ipsos Mori's tight filter on respondents' tendency to vote – which experienced an unusual reversal under the survey.

Usually Tory voters are more likely to vote than Labour, but the percentage of Tory voters saying they were certain to go to the polls at the next election fell from 67% to 57%, while the percentage of Labour voters rose from 60% to 63%.

Satisfaction with the government fell to its lowest point since the creation of the coalition, with just 26% saying they were happy with the government and 66% saying they were unhappy. Since January, support among Tory voters has fallen from 77% to 51%.

David Cameron's personal popularity has also fallen, with just 33% saying they are satisfied with the prime minister against 60% unsatisfied.

But Ed Miliband had little to celebrate, with a five-point reduction in his personal popularity to -18.