Education is a prerequisite for democracy, otherwise the people are all the more easily seduced by promises of wealth and riches for everyone without carefully considering whether it's realistic or not. Sure, that'd be great if everyone had everything they wanted (not just needed) but that can't be guaranteed. As you say, those who are looking to manipulate the vote take advantage of ignorance and education is a strong shield against that.

Your post is especially valuable because it challenges what I imagine is a key misconception of democracy - it's more than just votes. Otherwise there's a tyranny of the majority (where majority can be as simple as half + 1), who might decide they don't like some minority and punish them for not being the same. Checks and balances must exist to challenge and overcome an individual leader's desire for more power, but the form they take may vary. The American system of dividing the makers of the law; the executor of the law; and the judge of the law is the model I'm most familiar with but it has its flaws, for example, it seems all too eager to give the president more powers without properly constraining them...

But if education is a prerequisite for democracy, and the general population's education isn't very high (however that is judged), is democracy even an appropriate form of government? Singapore for much of its modern history was led by Lee Kuan Yew, who was very effective in leading its change from third to first world country however he certainly was more authoritarian than democratic. Some might say he was a model "benevolent dictator", while his tactics were harsh at times, he still delivered results with his preferred form of governing. But that also means that the dictator must actually care about the national economy and more, and most dictators don't seem to care enough to work hard on that...