Candidates aligned with Maduro have won 20 of the 23 governor posts and the mayorship of the capital Caracas in the face of a divided opposition running in an election for the first time in 3 years.
Luisa Ortega said on Monday that she will not recognise a new assembly voted in on the weekend, calling it an expression of "dictatorial ambition".
The escalation of deadly violence left at least six people dead overnight and into Sunday, according to prosecutors, adding to a four-month death toll approaching 120.
Accompanied by close advisors and state media, Maduro voted at 6:05 a.m. local time, far earlier and less publicly than in previous elections.
39-year-old lawyer Jose Felix Pineda, was killed from multiple shots fired by assailants who broke into his home overnight, prosecutors said.