On May 5, Warren County GOP primary voters will pick between a long-tenured incumbent seeking to keep his seat and the mayor of Lebanon to represent the Republican Party in the general election for county commissioner.
As part of its 2026 primary election voter guide, WVXU sent surveys to candidates in contested local races. Learn more about the candidates below. Candidates were given the same survey questions and word limit of no more than 250 words to respond to each question.
All candidate responses have been lightly edited for grammar and style.
Tom Grossmann
Campaign website: tomgrossmann.com
Biography
Tom Grossmann is an attorney who has served on the Warren County Commission for 12 years.
Why are you seeking a seat on the Warren County commission?
I am seeking a seat on the commission to continue to serve this county and its residents. I have a long and strong record of experience and success as a commissioner. I have a record of resident-friendly tax decisions that I want to continue. I have a background and record of supporting the farming and business communities of Warren County. I have a strong record of living and supporting conservative, Republican values. I have the education, background and experience that qualifies me to address the complex issues of a large county. For those reasons I am seeking another term as a county commissioner.
What is the biggest issue facing the county, and what can commissioners do to address it?
Warren County has been one of the fastest-growing counties in Ohio. In 2014 we had about 221,000 residents. In 2026 the county will have about 261,000 residents. Our population has increased by 18% in the last decade. In the next decade, we may have over 300,000 residents. To address this, we must have balanced residential and business growth. This requires careful planning, zoning, economic development and programs that maintain our current business community and which encourage new businesses and investment. Businesses bring in good, new jobs which support our tax base; fund needed infrastructure, road and utility improvements; and support our schools helping to keep taxes low.
I was on Mason’s council, as both a former mayor and vice mayor. I helped Mason grow its business base. As a commissioner, I have brought that same ability to the county. We are currently working on development projects in Franklin and at State Route 122 and Union Road.
Are there issues facing the county you see as very important that the commission can’t impact directly? How would you work with other entities — public or private — to address those?
I would like to see reform of our property tax laws with higher exemptions and lower property taxes for senior citizens, but it is not within the power of the county commission to make fundamental changes in property taxes. Consequently we are working with our state representatives to find a way to ease the property tax burden, particularly on our senior citizens.
The county commission already helps all county residents by keeping our county real estate taxes low. Warren County has an effective combined millage rate of 7.78, which is lower than Hamilton (25.76), Butler (12.13) and Clermont (10.7). We also have kept our sales taxes low at 6.75% (the same as Clermont County) while the rate in Hamilton is 7.8%, Montgomery is 7.5% and Clinton is 7.25%. Only Butler County has a lower rate of 6.5%.
Our primary current revenue sources are the sales tax and property taxes. If property taxes are abolished, the only current viable alternative will be an increase in sales taxes. It would have to be about 17% if the property tax is eliminated. About 70% of the property tax funds our schools. Warren County has some of the best schools in the state. The state legislature is working on those questions, and we are consulting with our state elected officials on this issue.
You’re a long-tenured incumbent in this position. What have you learned during your time on commission that makes you the best choice to continue with this role? What new goals or ideas do you have for another term?
I know how the county works, what its needs are, and how to increase the quality of county services without raising taxes. This requires the breadth of experience and knowledge I have learned as a county commissioner for more than 11 years. I have managed the county’s finances so it has no debt, has a $47 million infrastructure fund to cover capital needs, and maintains a $13.5 million rainy day fund. The county’s 2026 operating budget is $93.6 million, a decrease of 0.26% from 2025. I will maintain that level of success, maintain our top bond rating, and ensure that this county remains one of the best places to live in Ohio. Finally, I am dedicated to maintaining and encouraging our farming heritage and to preserve as many of our family farms as possible. I am the only farmer on the commission. I grew up on a farm in Hamilton County and still own and operate a farm there. I want to increase and support our county 4-H programs, expand our county fair, which celebrates our farmers and families involved in farming and 4-H. Nothing is dearer to my heart than this. I oppose selling our fairground to the city of Lebanon, which wants to develop much of it into high density housing and retail businesses. I want the fairground to be about farming, agriculture and nature.
For as long as I am a commissioner, I will do all I can do to maintain our farms, our rural character and traditions. This includes keeping our fair at its traditional site, improving it, and making it a year-round park for all the county to enjoy.
What past accomplishments should voters know about when considering your candidacy?
I have been a commissioner since January 2015 and have made a positive impact for the county and its residents. After I became a commissioner (1) our county earned Moody’s Ratings top bond rating (only three Ohio counties have that rating); (2) all county debt was retired (only eight Ohio counties are debt-free); (3) we gave county residents a real estate property tax break of $46 million in 2022 (and are seeking to do it again this year); (4) a new county jail and other new county facilities have been built (and we still have no debt); (5) we lowered the county sales tax; (6) we developed a sports park bringing in increased tax revenue; and (7) we kept the ATP tennis tournament in the county.
I have a proven record of accomplishment. My opponent concedes under my leadership we have “the best run county in the country” (February 10, 2026 Candidate Meeting with the Warren County GOP). Our county is ranked by U.S. News and World Report in the top 3% of all counties in the U.S.
Mark Messer
Campaign website: messerforcommissioner.com
Biography
Mark Messer is challenging Grossmann for his commission seat. He’s currently mayor of Lebanon. He’s serving his fourth four-year term on Lebanon’s city council.
Why are you seeking a seat on the Warren County commission?
I’m running because Warren County deserves leadership that is present, accountable and focused on results. For the past 14 years, I’ve helped lead the city of Lebanon through responsible growth: balancing budgets, investing over $100 million in infrastructure, securing more than $30 million in grants, $248 million in private-public economic development partnerships in the past five years, and reducing debt without raising taxes.
Warren County is at a critical moment. Growth is accelerating, costs are rising and decisions made today will shape the next generation. I’m stepping forward to bring proven, disciplined leadership to the county level.
What is the biggest issue facing the county, and what can commissioners do to address it?
The defining challenge is managing growth without losing what makes Warren County special. We’re one of the fastest-growing regions in Ohio. That brings opportunity, but also pressure on infrastructure, services and housing affordability. The growth that is coming to Warren County should work for its residents, not just happen to them.
My approach is simple:
- With thoughtful planning and collaboration identity investments zones
- Invest in infrastructure ahead of growth
- Strengthen and incentivize the commercial/industrial tax base
- Protect the character of our communities
Are there issues facing the county you see as very important that the commission can’t impact directly? How would you work with other entities — public or private — to address those?
Property taxes are one of the biggest concerns I hear from residents, and the system needs reform. The state legislature has provided counties with tools to help relieve the burden of property taxes and I support the use of those tools. In fact, I wrote a letter to my opponent months ago to advocate that Warren County, like our neighbors in Butler County, put those tools to work immediately to help cut property taxes. To this day, I have never received a response, and I am personally stunned that there have not been any steps taken to tackle this problem given the authority vested in them by the state. This lack of urgency is a problem I will fix.
Now when it comes to development, Warren County is special, [with] thriving communities alongside preserved rural areas. The goal isn’t to stop growth or push it blindly, it’s to guide it. We need thoughtful planning that protects what residents value while ensuring the county remains economically strong and affordable. That balance requires leadership that listens, plans and makes decisions with the long-term in mind. I am not interested in development for the sake of development, and I am not interested in preservation coming at the expense of a thriving county and economy.
You’re challenging a long-tenured incumbent for this position. How will you approach the role differently, and what do you hope to accomplish that your opponent hasn’t achieved?
This race is about accountability and priorities. My opponent has held this seat for 12 years and during that time, he has grown comfortable and unaccountable. He consistently misses meetings and has become disengaged and disconnected from the people he is supposed to serve. Government drifts from its core mission when elected officials forget that they are supposed to work for the people and not the other way around. That’s exactly what I’m running to change.
I’ll approach this role differently by doing the job the way it’s supposed to be done. First, by showing up, being accessible, and putting taxpayers first every single day. I've done that as the mayor of Lebanon. I have a track record of making tough decisions, managing complex budgets and staying accountable to the people I serve.
On Day One, I will use the authority already granted to the commissioners by the state to reduce the property tax burden in our county. I raised this issue months ago, and I was met with silence. That’s a problem. When the county stockpiles record levels of cash but won't relieve its residents from the crushing burden of skyrocketing taxes, it proves that they are out of touch with the people who live in our community. I will bring urgency, transparency and action back to this office. Warren County was built on hard work, fiscal discipline, and leaders who communicated and answered to their constituency; not closed groups and political activists. That’s the standard I’ll work to restore, and that’s how I'll make sure our county government once again works for the people.
What past accomplishments should voters know about when considering your candidacy?
Warren County is home. It’s where I grew up. Playing baseball in our parks, kayaking our rivers and spending time on our trails. It’s where I’ve built my business, served my community and started my family. With that in mind, I have been able to play a small role in the city that I love and call home. Here are just a few highlights.
- Legislated a reduction in property taxes by $1.82 million a 3 mil decrease.
- Sponsored participation in Ohio’s Open Checkbook regarding government expenses transparency program starting in 2013.
- Sponsored policy and legislation that led to over $30 million in grants awarded to the city of Lebanon in the past few years.
- Sponsored energy policy that has led to core municipal generation assets that save our electricity ratepayers millions of dollars relative to outside jurisdictions. The city of Lebanon maintains electric utility rates 37% cheaper than our competitors.
- Sponsored policy guidance [and] legislative initiatives that have paved the way to invest millions of dollars into our infrastructure. This has made it possible to maintain the growth trends of our city while protecting our waterways, greenspace and culture.
- With thoughtful planning and targeted investment, I helped deliver $248 million of private-public partnership in the past two years. This success was not overnight; it took years of planning ahead and collaboration.
- Sponsored legislation to pay off and refinance municipal bonds that saved the taxpayer millions of dollars.
Read more: