The runoff election is April 16. No Democratic candidates are in either race.
Stisher, 67, has served six terms as a commissioner, and Frost, 40, is a first-time candidate.
Stisher got 38.86% of the vote, followed by Frost with 32.89% and Gary Livingston with 28.25%.
Incumbent Abercrombie won 65.11% of the votes, followed by Keith Allison with 20.61% and Charles Pitman with 14.28%.
