Are voters really as well-informed as they think they are?

But are you working harder to keep yourself well-informed?
Since my return from Canada, I have been trying, but failing, to catch up on my last issues of The Economist before my subscription expires.
I was reading the special report published in the April 23rd issue on Democracy in California, and amongst all the generally very good articles about politics and democracy in California and America, this article caught my eye: how voters decide based on their limited amount of knowledge, which they think is sufficient to make a decision but think that their fellow voters are not as well-informed to make the same decision as they. I attempt to summarise the findings here, but you should read the original article for the full statistics and studies.
A survey of voters done in California apparently indicates that "fewer than half of respondents" have "confidence in their fellow voters to make public-policy decisions at the ballot box", which would naturally mean that they probably have more confidence in their own decision-making, that the decision they make is a well-informed one.
We learn in Economics that perfect information / knowledge can never take place because there will never fail to be gaps and loopholes in our knowledge (through breakdown / misunderstandings in communication for instance), which would then inhibit how we make decisions. So certainly there's no expectation for a voter to be omniscient. But how much information is sufficient for one to make a wise decision when voting?
A follow-up poll done indicates that many claim to have "'some' or 'a lot of' knowledge about how state and local governments spend and raise money". But when they were then assessed about their knowledge, i.e. asked to answer questions pertaining to various aspects of the state spending and budget, the percentage of voters who got it right (i.e. really know their stuff), suffice to say, are much, much lower than the percentage of voters who think they got it right (i.e. think they know their stuff but actually they dont).
But what's disturbing, according to the survey, is that apparently the older, more educated, wealthy and attentive voters are actually more prone to being misinformed or not have accurate understanding of the issues at hand. It is suggested that this is because of "self-interest" and maybe "a potential blindness to issues outside of one's own experience". Which probably means that someone who has the experience with the issue is more likely to fall back on what he observes in his experiences rather than what is truly the situation, which he might not have exposure to or knowledge of.
The article alludes to another reason for people not knowing their stuff - misinformation. Which is quite a valid concern in California, given that in the previous and subsequent articles there is a lot of talk about how interest groups with the most money flood the airwaves and broadband with their "misinformation". Which, when combined with ignorance or with the tendency to sympathise with your own beliefs, is a deadly combination for the polls. Plus it doesnt help that their official documents are dripping with "legalese" and obscurities.
Link back to Singapore. In the election that just passed, I have seen people who are either staunchly pro-PAP (People's Action Party, for our foreign readers) or staunchly pro-opposition. And when I ask them why, many of them quote from their own experiences to formulate their own stance and hence their own vote. So while in an ideal election people vote based on what is best for them and for everyone, on the basis that they are as well-informed as possible about the benefits, disadvantages and trade-offs of the various parties, it will never come to be an election that truly operates in this way, because we are all shaped by our experiences, thinking that we really know it all when in fact we just "know".
Which can apply to me as well. Do I really think I am well-informed when I write about this article questioning people's knowledge?
