Democrat Brian Matlock was leading the race for Arizona mine inspector as of Tuesday night, with a strong lead over Republican incumbent Les Presmyk.

Matlock, a mechanical engineer and Marine veteran, was beating Presmyk 54% to 46% as of 11:30 p.m., according to unofficial results from the Arizona Secretary of State’s Office. This places the race closer than other statewide races, where the Democrats’ leads are in the double digits.

The two candidates shared few policy disagreements, but the race centered on questions Matlock raised about his opponent’s small-dollar campaign contributions from individuals associated with the mining industry. Presmyk, meanwhile, raised concerns about Matlock’s qualifications for the job.

The result marks the first time a Democrat has held the post since 1976.

Matlock told the Arizona Capitol Times a win would demonstrate “how democracy can work” despite minimal spending by his campaign.

“What you’re going to find is a generational change,” he said.

He proposed updating the state’s mining code and securing abandoned mines through community engagement.