"The Congress may determine the Time of chusing [sic] the Electors, and the Day on which they shall give their Votes; which Day shall be the same throughout the United States."
I don't see anything which implies that a state has any say in the matter.
You do realize that this refers to the meeting of the Electoral College and not to the popular vote?
Some FReeper will know specifically, but I believe federal election days are determined by federal law.
No reason for the parenthetical “chusing [sic]” as it is recognized as archaic and correct spelling given the time.