If you look at the government's data, table 1.2, under the On-Budget Surplus / Deficit Column, you can see that Obama since 2008 has managed to double GW Bush's worse year in terms of a deficit. And everyone, including the OMB, believes the 2012 and onward projections to be fantasy. The reason you will need to use the data tied to GDP is because the comparison needs to have consistency from year to year in terms of how much money the federal government spent as a percentage of the country's gross economic performance.
http://www.whitehouse.gov/omb/budget/Historicals
http://www.whitehouse.gov/omb/budget/Historicals