Veteran Labor strategist Bruce Hawker says Bill Shorten needs to come up with better answers to the coalition's attack over economic management.
The Liberal Party on Monday launched a new television advertisement targeting Labor's handling of the federal budget, which concludes with the slogan, "The Bill Australia can't afford".
Mr Hawker said the economy was a "weak spot" for Labor in political terms.
"Labor has to answer that stuff about the economy, because it is a tough point for Labor always," he told Sky News.
He said the answer lay in Labor defending its role in getting Australia through the global financial crisis and pointing to the rise in government gross debt from $257 billion in 2013 to over $530 billion today.