Translation: states cannot tell electors how to vote. With no legal binding, electors can vote for their party's candidate instead of the candidate specified by the state.
And yeah, it affects winner take all states (48) - or would if it were the Supreme Court instead of a District Court. As it stands, it affects the Southwest.
Not likely to go to the Court this year - but it mucks up efforts to award all votes to the nationally popular candidate.
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