Grossmann pointed to the county’s low debt, property tax rates and overall financial health as examples of how well he and the other two commissioners had done over the past four years.
Maag said Grossmann, former county GOP chairman and Mason mayor, “must have a short memory,” alluding his 2014 successful run against incumbent Commissioner Tom Ariss, who had also served as the county sheriff.
Maag also said he was running in response to criticism from county residents who said Grossmann “doesn’t avail himself to the people of the county.”
The other two challenges come from relatively unknown Republicans.
Wilson, R-Hamilton Twp., appointed to the District 7 seat little more than a year ago, is opposed by Brad Lamoreaux of Lebanon.
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Lipps, R-Franklin, is opposed by Daniel Kroger of Clearcreek Twp. in his run for a second term.
Kroger and Lamoreaux are new to the political scene in Warren County, where GOP primary winners generally win in the general election.
The races all hinge on certification of nominating petitions by Feb. 19.
Maag, formerly R-Salem Twp., represented the 62nd District before being term-limited from this state office.
He pulled petitions to run for an open seat on the county commission two years ago, after Pat South announced her retirement.
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But Maag eventually backed Shannon Jones for the commission seat and was expected to be appointed, but was not, to the senate seat where she faced term limits. He also backed Lipps’ election.
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Wilson replaced Jones, who was elected to the Warren County Board of Commissioners as she faced her term limit in the Ohio Senate.
State Rep. Paul Zeltwanger, R-Mason, is unopposed in the May primary. Democrat Nikki Foster of Mason filed to run against him in November for the 54th District seat.
Democrat Sara Bitter of Loveland filed to face Wilson or Lamoreaux in November, according to an on-line list of candidates posted by the Warren County Board of Elections.
And just hours before Wednesday’s deadline, Jim Staton, a Democrat from Springboro, filed to run against Lipps or Kroger.