They are all held accountable by the same group of handlers. These are the same people who control the mainstream media, foreign policy, oil/gas/auto industry, etc. Believe me, not much is going to change for the better after anyone of them are elected (Clinton, Obama, Edwards, Romney, McCain, Huckabee). Even if a Ron Paul or Mike Gravel were elected, they wouldn't enough political muscle to make real changes that benefit the people. The wheels have been set in motion for a global government that will probably materialize during our lifetimes.