re: 3/4 of states approval to abolish the electoral college.
On adding States to Union — doesn’t that too, require 3/4 of the States approval. I just can’t believe the Dems could add Puerto Rico and D.C. just by Senate vote and Pres. approval. Do you know?
I think you’re right - they can’t add states with a bare majority. What they can do is eliminate all filibuster rules and vote to add 17 justices to the supreme court, but even that would be a hella battle.