Repeal the 17th Amendment.
With those two changes, we'd be back on track to having the Republic that our founders envisioned.
So outside of the limitations of the 15th Amendment and poll taxes, and the 26th Amendment, states still have wide powers to decide who can vote for Congressmen and Senators.
And . . . State legislatures can still appoint Presidential electors.
We have only ourselves to blame for this dangerous drift into democracy.