The Republican primary race between the two candidates for Natrona County Assessor is so close that the ballots must be recounted Thursday, the Natrona County Clerk said Wednesday.

The unofficial results as of late Tuesday night show Matt Keating  received 6,517, or 45.54 percent, of ballots cast, and Tammy Saulsbury received 6,401, or 44.73 percent, of ballots cast, County Clerk Renea Vitto said.

"Less than 1 percent constitutes a mandatory recount," Vitto said.

The GOP primary for Assessor was among the more hotly contested races in the county.

The assessor lists and values all real and taxable personal property in the county, and taxes paid on those properties affect the revenues for state and local governments, schools, and special districts.

Former County Assessor Connie Smith died in early April just a couple days after her retirement became formal.

Smith's retirement announcement prompted the Natrona County Republican Party's central committee to hold a special meeting  to select three candidates for the position. Saulsbury, assessor's office employee Shannan Robinett, and county commissioner Matt Keating applied.

The Natrona County Commission interviewed the three and appointed Saulsbury.

After her appointment, she fired Robinett and several employees who supported her.

Keating, a Natrona County commissioner, has been a longtime critic of the office, saying there have been inconsistencies in how properties are assessed, and the office needs a private sector ethic and the use of market information from the Multiple Listing Service to assess properties.

Vitto said the recount could take all day. Unlike races such as those for state House or Senate in which a limited number of ballots need counting, the Assessor is a county-wide race.

Of the total 16,388 ballots cast in the Natrona County primary, 14,309 were cast by Republicans. The rest were cast by Democrats and they will not be subject to the recount, Vitto said.

So all 14,309 GOP primary ballots must be run through the central counting machine on the second floor of the Old Couthouse upstairs from Vitto's office.

She and her staff will begin the recount about 8:30 a.m. and may not finish until 6 p.m. or 7 p.m., she said.

After the ballots are counted and the winner is determined, the county's canvassing board -- the clerk and two electors of different political parties -- will meet on Friday to certify the ballots, which will then be sent to the Wyoming Secretary of State's Office in Cheyenne.

The state canvassing board -- Gov. Matt Mead, Secretary of State Ed Buchanan, State Auditor Cynthia Cloud, State Treasurer Mark Gordon -- will meet Tuesday to certify the ballots for the official results, Vitto said.