A couple things are missing from these calculations. First is that much of the discretionary spending in the 2009 fiscal year wasn't passed until March of 09, meaning they carry Obama's signature. Second is that Obama voted for TARP, signed the Stimulus bill, signed those Omnibus portions of the 09 budget, and hasn't had a budget passed since then. If spending in his administration was really flat (it isn't) then nobody can claim the credit because the democrats haven't passed a budget in the Senate since then.
Actually since Bush’s TARP was paid back, the net was zero.