The document will flag a return to surplus by the long-established target date of June 2015.
The Treasury forecasts of revenue and spending on which meeting that target hinge are said to be far more credible than in preceding Budgets.
The sub-text of all this is to pose a simple question to voters: why would you change horses when the one you have been riding is delivering tangible results?
Two other factors make this year's Budget far more political than the normal steady-as-she-goes mid-term document which tends to be more of a holding operation so that there is money in the coffers in the following election year.
First, when it comes to spending on capital projects, English has the $1.7 billion proceeds from the float of Mighty River Power to play with. Some of that has been earmarked for a new $600 million public hospital in Christchurch. But English will still have a good chunk to distribute.
Second, Key and English have been hinting during the past week that the Budget will contain action on child poverty and other help for the poor.
This is classic Key. He is shutting down areas where National is vulnerable, while trying to silence Labour's claims that the Budget has been written solely for "Key's mates".
Doing something for those at the bottom of the heap is also an antidote to perceptions that when National is not selling something like Mighty River Power, it is busy selling out to the likes of SkyCity.
In that regard, today's Budget is all about softening National's image to hold on to the "soft" vote whose attachment to that party is weak.