The voters make decisions based on the information they are fed. Not the information they *GATHER* by and large, because that is an active process. Most people seem to tune in to the media outlets that favor their political leanings, which are driven by the corporate and special interests that own these media empires. Whether your corporation is Fox, MSNBC, or American Public Media, people are really being spoon-fed an official line that serves somebody else's self-interest, packaged in a way that makes them feel like this media empire puts its own self-interest below that of its audience.
Part of the problem is that news is a form of entertainment, and in the USA at least, news outlets are legally allowed to deliberately lie to you. Journalists are hypnotists, plain and simple, and if they do tell the truth it is because it happens to align with their employers' interests that day.
If people were given the tools to understand this game during their formative years, they might be more willing to take the time to independently research the issues they care about, but even this is a stretch. After a long day at the office, most folks want to just sort of zonk out and, tired and often filled with alcohol, the news is turned on and they absorb the day's "news" without a single functioning critical thought neuron in action.
If I were naive I would suggest some legislative fix to this but knowing how the legislative process works, and its typical results, this would almost inevitably lead to a much worse scenario than that which is being played out right now.