It has nothing to do with Sandra, and everything to do with the D.
Actually Fluke's only opponent is also a Democrat. Its a D vs D race in the general election.
I live in the district. So does my old, somewhat senile mother, who is a registered Democrat and gets a lot of fancy direct-mail campaign literature from Fluke. Someone is spending money for Fluke, probably Luke herself, and its probably her new rich husband's cash.
I'd say Fluke is likely really ahead. She is spending the money and has name recognition in Rat circles (Thanks Rush).