ORMOND BEACH - City Commissioner Bill Partington's plans to run for mayor will leave a vacant seat for Zone 4 commissioner in the 2016 elections.Planning Board member Harold Briley, a realtor with Adams Cameron, is the first candidate to announce his plans to run for the open seat but won't officially be able to file until next summer.Mayor Ed Kelley's announcement earlier this month that he will challenge Volusia County Commissioner Doug Daniels in the November 2016 elections set off a domino effect for political hopefuls.