Daniel Gross does the math:

While the national debt mounts, I’ve noted that the primary deficit—the annual mismatch between revenues and expenditures—is melting away. … Through the first six months of this fiscal year, revenues are $1.196 trillion, up 12.5 percent from $1.063 trillion in the first six months of fiscal 2012. Meanwhile, the government has spent $1.797 trillion in the first six months of fiscal 2013, down 2.4 percent compared with the first six months of fiscal 2012. The deficit for the first half of the fiscal year is $600.5 billion, down 22.5 percent from $775 billion in the first half of fiscal 2012.

If the Obama budget were implemented, and if current trends continue, the deficit will have come down by 47 percent in four years. In relation to GDP, it will have declined from “10.1 percent of GDP in 2009 to a projected 6 percent in fiscal 2013 (it’ll probably be less), and 4.4 percent of GDP in fiscal 2014.”

And Obama has managed this while not crippling economic growth, as in Europe, and without a Grand Bargain. If the GOP responds to his new budget by taking yes for an answer, he could do better.