Yes, Labour should be more ahead in the polls, but they are doing better than they did in the last election under Jeremy Corbyn. And the Conservatives would love someone like Jeremy Corbyn to be in charge of Labour, which is why so many joined Labour to vote for Corbyn, some voting three times!
There is an argument that Keir Starmer should be more vocal about his opposition to Conservative policies, but I think that he is right in being cautious about opposition for oppositions sake. In PMQ's, the Prime Minister has repeatedly misrepresented his past positions in matters and these, in the build up to an election will gain the Conservatives votes. When Keir Starmer has made mistakes about past positions, the media rightly hold him to scrutiny on this, but much of the media ignore the way Boris Johnson lies, or "inadvertently" misrepresents the truth on many occasions in PMQ's.
For just £3 you can help destroy the Labour Party... vote Corbyn #ToriesForCorbyn
— Michael Green (@ToryForBritain) June 15, 2015
The bottom line is that Labour is better in the polls than they would be under Jeremy Corbyn. As to if this will be enough in the next general election, only time will tell.