After the Party — a Convention.

"The Congress, ... on the Application of the Legislatures of two thirds of the several States, shall call a Convention for proposing Amendments, which ... shall be valid to all Intents and Purposes, as Part of this Constitution, when ratified by the Legislatures of three fourths of the several States or by Conventions in three fourths thereof, as the one or the other Mode of Ratification may be proposed by the Congress;" Article 5, U.S. Constitution.