Republican challenger Chuck Stuber led incumbent Democrat Beth Wood in early results.
Stuber held an advantage, 904,879 to 875,086, with about 27 percent of the ballots cast.
Democrat Beth Wood is running for a third term as state auditor.
Republican Chuck Stuber, a former special agent for the FBI, is challenging her.
About the office
The winner will lead the Office of the State Auditor, which is supposed to ensure public money is properly accounted for, reported and managed. The office has broad powers to examine all books, records, files, papers, documents, and financial affairs of every state agency.
What shaped the race
The race pitted experience versus the promise of change. Wood campaigned on her track record and her ability work with Democrats and Republicans. Stuber is new to politics, which he calls a positive. He promises to bring a different perspective and fresh ideas for preventing fraud and waste.