The recount that will determine control of the Virginia Senate begins at 8 a.m. Monday.

Del. Lynwood W. Lewis Jr. (D-Accomack) was certified by the State Board of Elections Jan. 10 as the winner of the race to replace Lt. Gov. Ralph S. Northam (D) by just nine votes out of more than 20,000 cast. That slim margin entitled Republican Wayne Coleman, a shipping company owner, to request a recount paid for by local governments.

With Democrats on Tuesday keeping the seat previously held by Attorney General Mark R. Herring (D), both parties are now focused on Northam’s district, which includes part of Hampton Roads and the Eastern Shore. If Democrats hold both open seats, then Northam would serve as the tiebreaking vote in the 20-20 chamber.

Each locality in the district will recount its ballots beginning at 8 a.m. Monday, with representatives from both campaigns on hand to observe. Any ballots on which local officials cannot agree will be sent to a special three-judge panel meeting in Virginia Beach to resolve.

A similar procedure unfolded on a statewide scale last month, as Herring’s victory in the attorney general race was also decided by a recount.