I believed this happened in the union recall of Walker. The last place to call in was a deep Republican state and they called in a huge number, ultimately making the number for the Democrats to make up unreachable. The Democrats were fit to be tied over it.
“state” = “district”
It was actually the Supreme court race. Waukesha country reported the results properly, but there was an error/oversight/strategery, where they failed to report their totals to the AP, which then had lower numbers for the Republicans. The holdout Dem precincts then reported, putting Justice Prosser behind. Once the Waukesha results were corrected it was too late for the Dems to steal it and Prosser won.