So a Demon Rat governor appoints her replacement. Probably the Demon Rat running against Kari Lake.
She's not resigning, she's ending her re-election campaign. She wasn't going to win, so she's bowing out. The race is now between Gallegos and Lake, with Gallegos appearing to be well ahead in polling. Arizona is turning blue. Lake's best hope is a big turn out for Trump, while unenthusiastic Biden voters don't vote at all.