The Oldham East and Saddleworth by-election was undoubtedly a positive step forward for Labour but the champagne should remain on ice until tougher battles are overcome.
The last time a governing party captured a seat in a by-election was a Tory victory in 1982 under Margaret Thatcher.
With the country battling an economic crisis, unemployment rising and deep cuts announced for the public sector, anything but a victory for the opposition would have been an abject failure.
Labour leader Ed Miliband was quick to proclaim this as a verdict on the Government, but Oldham East and Saddleworth has been a Labour seat ever since it was created in 1997 and in 13 years the only realistic challengers have been the Lib Dems. This was a verdict on Nick Clegg, not David Cameron.
Mr Clegg's party is divided. Many activists are angry about the U-turn on tuition fees, effigies of the Sheffield Hallam MP are being burnt on the streets and the few Ministers they have are struggling to support Government policy.
It was no accident that the runner-up, Elwyn Watkins, had precious few references to his party on his campaign literature. It was "vote for Elwyn", not "vote Lib Dem".
The Tories had little chance of winning but, having conducted such a quiet campaign, will have their own questions to answer after candidate Kashif Ali lost 7,000 votes in six months.
However, it is the Lib Dems who are taking most of the flak. They stand accused of abandoning their principles in the pursuit of power and many voters, rightly or wrongly, see them as a political shield for the spending cuts. To fight back Mr Clegg must convince the public of his party's impact while in Government. If he fails the party may never recover. They cannot continue to sustain this much damage for another four years and survive.