IMO that's why the 'fix' of just removing the cap isn't going to work.
They won't remove the cap, no one other than the fringe is even talking about that. The reason is because Social Security has never been a welfare program, and lifting the cap without commiserately exploding the benefits received by those who pay on monster incomes would turn it into welfare.
That is the reason that weather you make a billion dollars or $20,000, you only pay tax on X amount of income with set benefit levels depending on your contribution. It has never been a plan to re-distribute wealth, contrary to what many people think. If you pay more because you have a higher income, you get a higher benefit.
Conservatives and liberals don't philosophically agree on the very nature of the program, but for the most part it is remained incredibly stable and insulated from political attacks because it is not a welfare/redistribution program. It polls very high with the American people and always has.
Politicians however know that attitudes towards it would change tremendously if you eliminated the caps on income, and then turned it from what it is into a wealth transfer program. I know some people are paranoid and have convinced themselves that it is the secret plot, but it is not on the table in any way.
Most likely the cap may go up a bit, but it won't be a massive number. The other idea I have heard tossed around is to start to increase the retirement age by 1 month a year, starting with a certain age (probably those under 50 years old) as that would be a realistic way to phase in the changes without really turning the program upside down.
2015 has long been the year that yearly inflows go negative, so it is a little ahead of schedule. The one quasi bright side to the doom and gloom crowd is that even if the government defaults on the S.S surplus trust, the yearly inflows from workers would still cover 75% of promised benefits. When you get past all the rhetoric, Social Security is actually in decent shape and can be fixed with a few tweaks to the current set-up.
If you listen to Greenspan, the debt commission guys and the talking heads, everyone is in agreement for the most part that S.S is the easiest to fix by making small tweaks to the formula as far as future benefits, retirement age, amount subject to the income cap and the employer/employee contribution. No different than what Reagan did 25 years ago.
As I said, S.S is the easy one. Medicare is the one no one wants to talk about, nor does anyone have any good solutions for.