Less than three months before the midterm elections, the Suffolk voter registrar resigned abruptly earlier this month, a member of the Electoral Board said.

“She decided to resign for personal reasons,” said David Sylvia, secretary of the Electoral Board. “I’m not at liberty to discuss any of the details or any of the reasons for her choice.”

Sharon Thornhill had worked for the registrar’s office for about 25 years, Sylvia said. She had been in the position of registrar for about two and a half years.

Sylvia said the board would move quickly to find a replacement. The registrar is appointed by the three members of the Electoral Board, who in turn are appointed by the Circuit Court judges.

“We’ve already been in contact with human resources, and we’ve been making up a job description to post,” Sylvia said. “We’re probably looking at two weeks to get resumes in.”

“We have an election coming up, so we need to not waste a lot of time.”

The Electoral Board and registrar have a busy election season ahead. A total of 17 candidates are running for City Council and School Board seats in four of the city’s boroughs, and the 4th District U.S. House of Representatives seat is up for grabs, with incumbent Randy Forbes fighting challenger Wynne LeGrow.