The natural counterforce to corrupting influences, all of them rather than just campaign finance, is robust citizen accountability. Clearly this accountability has left something to be desired. I would argue this has largely to do with rational ignorance (http://en.wikipedia.org/wiki/Rational_ignorance) on behalf of voters, that they, having so much to do, aren't willing to wade through the maze of political discourse in order to really know who is worth voting for.
But what if it was dead-simple to know where your rep stood, on every issue, not just the obvious ones, and on every level, not just congress?
I'd argue that with ease, you could convert a substantial number who currently don't case votes, or else default to simple heuristics in deciding who to vote for: e.g. party or incumbency.
To that end, I've started a site: http://votereports.org which aims to be something like the github of political accountability. A simple, decentralized group of folks generating, exchanging and refining politician report cards based on objective criteria such as votes.
The project is just 2 months old, and there's plenty to do, but it should be ready well before November.
For better governance, I'd stake my bet on this before I would on a constitutional amendment or change of heart for politicians. After all:
> "If a nation expects to be ignorant and free, in a state of civilization, it expects what never was and never will be." - Thomas Jefferson
Really, can we expect to do very much better, in a world where we collect, analyze, and share more data on baseball than on our own government? (http://radar.oreilly.com/2009/12/government-20-five-predicti...)