We don’t need the Senate to agree with it. It can be done by Constitutional Convention, if 33 State Legislatures vote for it. The proposed amendment will be presented to all 50 states to vote on. Then, if 38 states approve it, goodbye 17th Amendment.
Can you even imagine what any Constitution that came from a modern constitution convention would look like?
By the time it was finished, this country would be ruled by a class of people that makes this bunch today look like small letter democrats. It would be much closer to Germany or Russia in 1939. Probably even worse.
This has about as much chance of happening as Karl Rove becoming an FR moderator.