I haven't read the thing yet.
I'd say if you want to see how feasible it is, look at our federal budget but strip out the huge one-time items such as the bailouts and the stimulous plan and see what we've got.
I'm too lazy to rework 2009 etc, so I'll use the 2006 & 2007 budgets :
Both have total Revenue of about $2.5 trillion.
Both show total Expenditures of about $2.7
Both show a deficit of about $250 billion (due to roundng above my math doesn't quite add up, yet both years do come in at about this deficit amount). BTW: This is slightly less than the amount the gov gives for foreign aid which in 2007 & 2008 was about $275 billion.
That's about 9%. I.e., a budget cut of 9% would balance it. That, in and of itself, is a do-able number.
But those are pre-recession numbers, I don't see how it's really do-able, or desirable, in a recession (But wait! That's over, right?

). Also, any tax cuts would have to factored in, and we'd need to have them scored before having an idea of their impact.
These numbers come from Wiki, btw.
Also, it's not clear if the cost of Iraq & Afganistan are included. If not, the CBO estimated those at $115 billion for 2007. So if not included in the above amounts our 9% number would increase to about 14%. Iraq war costs may be significantly less now as it's wound down. They need to wind down Afganistan, and the repubs could probably get away with it without much political problems.
So, while it may not be easy I think it's do-able. But while we're in a recession I'd rather they just freeze spending and not cut it.
Fern