Bing Judd, who has been a Coos County Commissioner since 1997, has lost his seat by five votes.
Judd had 592 votes compared to 597 for challenger Rick Samson, deputy secretary of state David Scanlon told NHPR Thursday afternoon.
Late Thursday Judd said he will be driving to Concord Friday to file a request for a recount.
"Five votes in 1,200, there could be a mistake," he said. "It could go either way."
That recount is expected to occur Monday.
Judd had not faced a challenge for more than a decade.