The individual citizen has no federal constitutional right to vote for electors for the President of the United States unless and until the state legislature chooses a statewide election as the means to implement its power to appoint members of the Electoral College.
http://www.law.cornell.edu/supct/html/00-949.ZPC.html
That’s correct. Each state gets presidential electors. How those electors cast their vote is up to the state to decide.
That's what the Constitution says.