McCain has ruled out any new Social Security taxes, while Obama has expressed interest in boosting the cap by 2 percentage points to 4 percentage points for workers earning more than $250,000. The current 12.4 percent payroll tax that goes into Social Security is split between employer and employee.

The usual Washington way of making such unpopular changes is to have a bipartisan commission make recommendations, a method used successfully in 1983. The result raised Social Security taxes and trimmed benefits, and the system's solvency was significantly strengthened.

Many analysts believe that a commission is a viable idea. "A lot of members of Congress are ready to work together on this, but they have to be assured no one is going to try to double cross the other person," said Maya MacGuineas, president of the Committee for a Responsible Federal Budget. LINK