Labour and the Tories are virtually neck and neck in the wake of George Osborne's Budget, according to two polls.
Research by Survation for the Mail on Sunday put Ed Miliband's party on 35%, up 1% on their rating in January.
But the Tories have surged by 4% to 34% - effectively level pegging when the margin of error is taken into account.
The shift appears to have been at the expense of Ukip and the Liberal Democrats, who were both 3% lower on 15% and 9% respectively.
The online survey of 1,000 adults was carried out on Thursday and Saturday, after the Chancellor delivered his well-received package including a major pensions and savings shake-up.
Another post-Budget poll, by YouGov for the Sunday Times, also found the Conservatives were a single point behind, on 36% to Labour's 37%. It is the smallest advantage the firm's research has shown for five months.
Labour backbencher John Mann told the newspaper Mr Miliband needed to " speak the language of voters in Bassetlaw not academics in Hampstead".
He said: "It's talking clear, simple language that people understand. It's all too clever at the moment.
"A reshuffle of his speechwriters would help."
He added: "What the Labour shadow cabinet should do is get out of its policy committees and get out onto the doorstep and listen to the experiences of Britain's people."
Shadow business secretary Chuka Umunna said the Labour leadership would not be doing its job properly if all it focused on was day to day polling.
"Polls go up and down, we have seen them fluctuate... what matters is how people vote," he told the BBC One Andrew Marr programme.
"We have seen under Ed Miliband's leadership the Labour party put on over a 1,000 extra councillors, importantly in the marginal seats we need to get a majority at next year's general election.
"We have put on tens of thousands of new members since May 2010 and, of course, let's not forget what people were saying in May 2010 - they were writing the party off - p eople are seriously talking about us actually winning this year and that is not what they were doing in May 2010.
"What we are focused on is actually talking to the issues that matter to people."