I'm always stunned to hear when people say things like "The Democrats (usually Obama) haven't given their plans for X." Here's something to chew on: just because you haven't heard a candidate say something on a particular topic, doesn't mean they haven't said anything on that topic.
Just go to the website, people. Barack Obama's website (the admittedly difficult-to-remember
www.barackobama.com) clearly states that he wants to raise the cap on the FICA tax to help pay for Social Security. Edwards is the same. Not only that, Obama's and Edwards's websites are really easy to navigate.
(In contrast to Hillary Clinton's, apparently, where two minutes of searching didn't give me what I was looking for. So forget her!)
Cleo