There's been a growing movement lately suggesting that the 17th Amendment, which provides for the direct election of senators, should be repealed. For a "let's repeal and amendment" call, it's not actually that crazy.
Just look at judges. There's some arguments for having elected judges, but also some very good ones for having them be appointed. Likewise, goes the theory, we might be better off having one of the two houses of Congress not directly elected by the people, but rather one step removed, so that members of the senate could be chosen by a slightly less politicized method.
But, that's not what Michael Mannheimer (Northern Kentucky) is talking about. He thinks there's an argument that the 17th Amendment is unconstitutional. It goes basically like this:
Article V guarantees all states equal suffrage in the Senate. For those of you unfamiliar with our founding document, Article V sets out the rules for amending the Constitution. So, Article V is basically saying that no amendment can deny states their equal suffrage.
The next piece of the argument is that "the states" and "the people" are different under the Constitution. Not really a controversial point of view.
So, the 17th Amendment takes the states' representatives in Congress and gives those seats to the people. Senators are now chosen not by the state, but by the state's citizens, and that's a pretty important distinction.
The real key to Mannheimer's argument is interpreting "equal suffrage." Since no states can appoint senators, they are all equal. But, Mannheimer argues that the equality and suffrage parts are two separate concepts. The states cannot be denied equal standing with the other states, nor can they be denied suffrage.
Interesting to think about, but entirely academic. No Supreme Court would ever strike down a constitutional amendment.