In a post-Citizens United world, every election is rigged.
Not necessarily by funny business with voting machines, which I am sure exists and will continue to exist, especially in very close elections, but by money.
The fascist plutocrats are willing to spend however many billions it takes to catapult the lies and propaganda. Given the percentage of the electorate that is very low-information or just plain to-the-bone bigoted and/or stupid, it is, for the most part, easier to manipulate these sorry sheeple than to rig the mechanisms of voting themselves and lower risk. It is merely a cost of doing business, which will be handily recouped many times over once they have complete control and can finish their looting the 99%.
What can be done to reverse or stop this? As far as I can see at this moment, not one thing, for when money is speech, the rich can easily drown out everyone else and when there is such a significant uninvolved/imbecile segment of the electorate more than willing to be led to their own slaughter and resistant to any form of facts the tool of reason is a very small slingshot indeed.