"Public ignorance is disconcerting. But it also poses a serious challenge to democracy. According to the most popular theories of democracy, the government’s legitimacy depends upon the freely given and informed consent of its people. So democracy requires there to be regular free elections; such episodes are supposed to reveal the Popular Will, which provides government with clear directives for the exercise of power, thereby ensuring political legitimacy.
But if ignorance is as extensive as the data suggest (and losing parties comlain), elections could not possibly serve the function of expressing informed consent. Lacking adequate knowledge of how government works, citizens are unable correctly to assign responsibility to particular office holders for public policies enacted in their name, and consequently are unable to provide the necessary directives. That is, under conditions of widespread citizen ignorance, elections do not express the Popular Will; rather, they simply place some in office and remove others, willy-nilly. Elections, then, are exceedingly costly public events that achieve nothing more than what could be accomplished by a coin-toss..."continues at 3quarksdaily
*Also, don't overlook their Reasonable Atheism: a moral case for respectful disbelief, among many other masterful (and sometimes provocative) collaborations.