It is popular among Washington elite types to tut-tut criticisms of the plan put forward by Representative Ryan and the Republicans to replace Medicare with a voucher program by claiming that "at least he has a plan." This is supposed to be in contrast to President Obama and the Democrats who have no plan to deal with Medicare's projected shortfall.
It's possible that these Washington insiders missed it, but President Obama and the Democrats pushed through a piece of legislation called the "Affordable Care Act." This bill proposes a number of mechanisms for containing costs within the Medicare program. As a result the projected shortfall has fallen by almost two-thirds, from 3.88 percent of taxable payroll in the 2009 Medicare Trustees Report to 1.35 percent of taxable payroll in the 2012 Medicare Trustees Report.
People can criticize the mechanisms the ACA put in place or complain that they did not go far enough, but to claim that President Obama and the Democrats did nothing to address the projected shortfall in Medicare is not true.