As of 2010, approximately 49 million adults and children were covered by Medicaid and SCHIP. This number is expected to swell by 15 - 20 million on January 1, 2014.
Covering 49 million individuals requires about $283 billion annually. Adding another 15 million+ people will cost at least another $15 billion.
In 2011 the federal government spent $3.6 trillion for all aspects of government. That is 24% of GDP.
Of that, only $2.2 trillion came from tax revenues and interest earnings. The other $1.4 trillion was borrowed.
As Bill Clinton so famously said, the numbers don't add up. It's arithmetic.