The field for the 2012 Hamilton County Commission District 3 special election changed this week.

Democrat Mitzi Yates picked up a petition, and Republican Greg Martin has decided not to run.

That now leaves Hamilton County Pachyderm Club President Marty Haynes and interim County Commissioner Mitch McClure facing off in the March Republican primary.

Yates is the only Democrat who's picked up a petition so far, said Charlotte Mullis-Morgan, elections administrator. The qualifying deadline is Dec. 8 at noon.

"I decided to run because I am an ordinary citizen who tries to survive every day," said Yates, who works in claims for BlueCross BlueShield of Tennessee. "There's a voice that's missing."

Yates is one of about 700 voters who were moved from District 1 to District 3 after the commission redrew political boundaries based on 2010 U.S. Census numbers.

Last week, commissioners voted to run next year's primary based on the new lines, though the lines usually don't have to be in place until the fall elections.

Yates, 47, graduated from Hixson High School and now lives in the Dallas Bay area. She graduated from the University of Tennessee with a humanities degree and has a 10-year-old son.

She said she wants to improve relations among the county bodies, including the sometimes rancorous relationship between the County Commission and the Hamilton County School board.

"I do believe the school professionals are able to govern themselves," she said.

Though three candidates have signaled their intent to run, only Haynes has qualified.

McClure is currently serving as his own treasurer, but said he plans to officially name David Queen to the post, he said.

McClure was appointed by commissioners in January as a replacement for former District 3 Commissioner Jim Coppinger, who was appointed county mayor when Gov. Bill Haslam selected former Mayor Claude Ramsey to be deputy governor.