> It ultimately works off the issue that most voters are disengaged, while the most interested parties are very engaged.
That, and the fact winning a senate seat costs on average $26.53 million [1]
You can't self-fund, that's 152 years of your $174,000 salary.
Where do you suppose the money comes from, and what do you suppose motivates the donors?
[1] https://en.wikipedia.org/wiki/Campaign_finance_in_the_United...