It’s not a theory though; it’s actually written in the Constitution.
Congress has the authority to pass election laws if necessary to amend a given state’s current laws, but otherwise it’s a state issue.
Finally, the Court has recognized that because the Elections Clause specifically vests Congress and the states with authority over the Time, Places and Manner of congressional elections, the Court’s authority over such matters is limited.
It’s not a theory though; it’s actually written in the Constitution.
Congress has the authority to pass election laws if necessary to amend a given state’s current laws, but otherwise it’s a state issue.
Here’s an excerpt from the ArtI.S4.C1.3 Congress and Elections Clause that explains how the Supreme Court’s role works: