The urgent need to revitalise Labour's campaign and get on the offensive was underlined by last night's 3 News-Reid Research poll. Slipping to just over 26 per cent support, Labour failed to benefit from a small drop in backing for National. The winners were New Zealand First and Colin Craig's Conservatives who came close to clearing the 5 per cent threshold for the first time.
Labour's campaign seems to be lacking in urgency. The party is reactive, rather than proactive.
Labour deserves credit for the breadth and depth of its policies. The party is to be applauded for detailing exactly how those policies will be funded - even if that exercise was in part undertaken to avoid Cunliffe falling victim to John "show us the money" Key who skewered then leader Phil Goff over the cost of Labour's promises during the 2011 campaign.
It is also to Labour's credit that it is prepared to promote policies - such as introducing a capital gains tax and raising the retirement age - which carry political risk, but which the party believes are in the national interest.
But it seems that taking such risks - plus the party's recent bouts of indiscipline - have resulted in the adoption of a safety-first culture which is sucking the vitality and spontaneity out of Labour's campaign. It is about as exciting as a wet weekend in Westport.
Cunliffe can go a long way to changing perceptions of him and Labour tonight. Helen Clark did exactly that during equivalent debates in 1996 and never looked back.
Rather than the bombastic, lecturing figure that usually fills their screens, voters need to witness the more subdued, more relaxed, more empathetic and consequently more impressive Cunliffe who appeared in Labour's 14-minute election broadcast last Saturday night. It was a very different Cunliffe - one voters may yet warm to.
Cunliffe does not have to win tonight to put a fire under Labour's campaign. But he cannot afford to end up being rated the loser.
There is nothing like as much pressure on Key to perform. He is the known quantity. The pressure is heaped on Cunliffe's shoulders.
Tonight's debate will be the test of whether he can handle it - as it should be.