[pessimizer]

This the easiest and most realistic step in my opinion; the people lobbying heavily to preserve the current Senate system would just be entrenched local tyrants. I think the vast bulk of Americans would be swayed by the idea of having at least one Senator who almost completely shares their politics.

If the result is that the Senate becomes the most interesting and representative body, gradually shift the bulk of power there on whatever issues it's best at. If the result is that the Senate becomes a disaster, abolish the entire body.