I’d have to go with Aaron Burr. Tried to cheat Jefferson out of the presidency, take US territory and make himself king, and killed Hamilton in a duel.
However, I wouldn’t quibble with “2nd most corrupt:.
Burr’s my go to guy for worst man ever to seek high office in our nation’s history. I think Gore Vidal, a descendant of Burr, tried to rehabilitate his image. He failed.