By singling out Democrats, are you claiming that the Koch brothers and Sheldon Adelson haven’t influenced the government in ways that are beyond the scope of what citizens should be capable of?
The influence of the Koch's or Adelson is largely hinged on the fact that Americans don't use critical thinking when consuming their media. Rather than trying to find a way to wiggle around the first ammendment when it comes to spending on speech, why not try to build an electorate capable of critical thinking? If you don't think that's possible, then what's the point of any of this?