I wouldn’t be too sure:
How National Popular Vote Works
Winner-take-all is not in the U.S. Constitution, and not mentioned at the Constitutional Convention.
Instead, the U.S. Constitution (Article II) gives the states exclusive control over the choice of method of awarding their electoral votes—thereby giving the states a built-in way to reform the system.
“Each State shall appoint, in such Manner as the Legislature thereof may direct, a Number of Electors….”
The National Popular Vote law will take effect when enacted by states with a majority of the electoral votes (270 of 538). Then, the presidential candidate receiving the most popular votes in all 50 states and DC will get all the electoral votes from all of the enacting states. That is, the candidate receiving the most popular votes nationwide will be guaranteed enough electoral votes to become President.
Under the National Popular Vote law, no voter will have their vote cancelled out at the state-level because their choice differed from majority sentiment in their state. Instead, every voter’s vote will be added directly into the national count for the candidate of their choice. This will ensure that every voter, in every state, will be politically relevant in every presidential election—regardless of where they live.
The National Popular Vote law is a constitutionally conservative, state-based approach that retains the power of the states to control how the President is elected and retains the Electoral College.
National Popular Vote has been enacted by 16 states and the District of Columbia, including 4 small states (DE, HI, RI, VT), 9 medium-sized states (CO, CT, MD, MA, MN, NJ, NM, OR, WA), and 3 big states (CA, IL, NY). These jurisdictions have 205 of the 270 electoral votes needed to activate the law.