Georgia Secretary of State's power to enforce the 14th amendment of the US constitution re. deny Marjorie Taylor Green's right to run for re-election?

In CNN's Attorney grills Marjorie Taylor Greene about her false stolen election remarks at about 03:35 reporter Amara Walker says:

Now the judge is expected to make a decision early next month on whether or not Marjorie Taylor Green should be disqualified from running for re-election, he will make his recommendation to the Georgia Secretary of State who will then make a final determination.

Now Kate keep in mind that this insurrection disqualification clause in the 14th amendment is from the Civil War era, so that means that this provision has never been tested in modern history. And that will make it likely an uphill battle for the challengers.

Question: From where does the Georgia Secretary of State derive power to enforce the 14th amendment of the US constitution in the context of potentially denying Marjorie Taylor Green's right to run for reelection?

Certainly state authority is what one would expect applies to an individual's running in an election to represent that state, but is there a law in Georgia that says in effect 14th amendment challenges to a citizen's right to run for congress shall be heard by a judge who then makes a recommendation to the Secretary of State of Georgia who can simply decide to prevent someone from running by themselves?

This seems a bit tricky - is this current challenge following a codified procedure or is it somewhat ad hoc?

Note that answers to Who enforces the insurrection rules in the 14th Amendment, section 3? don't really seem to apply or fit in this case; and there's no mention of a Secretary of State of an individual state.