It takes two thirds of the states to vote to conveign a constitutional convection for the purpose of changing the constitution, not by popular vote.
Eligible is not equal to qualified. SCOTUS has opined Congress is not Constitutionally authorized to enlarge or abridge the rights of a U.S. citizen with respect to citizenship status. So, a Congressional vote to affirm a presidential candidate as qualified is not a vote to affirm the eligibility of the candidate.
The Constitution clearly states a President shall be a natural born citizen. A natural born citizens is a subset to a native born person which is seperate and distinct from a naturalized U.S. citizen. The Electoral College system was installed to prevent the American people and the States from electing an ineligible President. Electors may vote faithlessly, or not, to preserve and protect the Constitutional Republic. In Obama’s case, the Electors chose to elect President Obama while there were numerous individuals publicly complaining he was ineligible.
The US federal government is a servant of the people and the States. The US federal government is not Constitutionally authorized to prevent the will of the majority of the American people and the States. A naturalized citizen is qualified to be President if he/she receives a majority of the Electoral votes, but that does not equate to eligible.
The President is the US federal government’s chief executive officer. The President maintains the US Constitution and all other US law, treaties and executive orders in the Archives as evidence of law. An ineligible President breaks the chain of custody of evidence of law to void it. An ineligible President cannot maintain the Constitution while violating the Constitution.
The Articles of Confederation was repealed and replaced by the US Constitution. The Articles of Confederation required all states to ratify an amendment to the Articles of Confederation. Consequently, Article VII fo the US Constitution only required nine states to ratify the US Constitution and repeal the Articles of Confederation. The people can determine how and why their national government shall operate. Of course, those with a vested interest in maintaining the status quo will strongly resist.