The case does NOT have to wait until a candidate wins the election before a decision can be reached.
***But... can we time it so that it gets decided in October? ;-)
It can be done that quickly any time it's needed. Witness Bush v. Palm Beach Canvassing Board, 2000, which went through the Supreme Court twice in two months. Time to act is not a problem in such cases.
BTW, I filed successful Supreme Court briefs in both of those cases, so I know this can be done.
John / Billybob