Welfare spending has grown substantially over the past four years, reaching $746 billion in 2011 — or more than Social Security, basic defense spending or any other single chunk of the federal government — according to a new memo by the Congressional Research Service

The steady rise in welfare spending, which covers more than 80 programs primarily designed to help low-income Americans, got a big boost from the 2009 stimulus and has grown, albeit somewhat more slowly, in 2010 and 2011. One reason is that more people are qualifying in the weak economy, but the federal government also has broadened eligibility so that more people qualify for programs. Overall, welfare spending as measured by obligations has grown from $563 billion in fiscal 2008 to $746 billion in fiscal 2011, or a jump of 32%. The CRS numbers tell a complex story of American taxpayers’ generosity in supporting a varied social safety net, ranging from food stamps to support for low-income AIDS patients to child-care payments to direct cash going from taxpayers to the poor. By far the biggest item on the list is Medicaid, the federal-state health program for the poor, which at $296 billion in federal spending made up 40% of all low-income assistance in 2011. That total was up $82 billion from 2008. Beyond that, the next big program is food stamps, at $75 billion in 2011, or 10% of welfare spending. It’s nearly twice the size it was in 2008 and accounts for a staggering 20% of the total welfare spending increase over those four years. Several programs to funnel cash to the poor also ranked high. Led by the Earned Income Tax Credit (EITC), Supplemental Security Income and the Additional Child Tax Credit (CTC), direct cash aid accounts for about a fifth of all welfare.