What if only registered voters were allowed to make political campaign contributions?

There’s a lot of concern out there about the huge sums of money that corporations can pump into political campaigns. And a lot of hay has been made both for and against ever since the U.S. Supreme Court ruling that lifted the ban on corporate spending in elections.

This discussion is not about that.

Instead, I’m curious about one action that could be taken to rectify the perceived injustice and yet maybe also address the underlying tenets of both sides. Specifically, I think elections should be about the voters. And I was wondering what harm we might run afoul if we only allowed people qualified to vote to actually make financial contribution to the process? Also, what good do you think might come of it?