Democrat Jennifer Boysko has formally filed a petition for a recount in last month’s tight election for the 86th District seat in the Virginia House of Delegates.

After 21,000 votes cast in that Nov. 5 election, the state board of elections declared Republican Tom Rust (R-Fairfax) the winner by just 54 votes, or a 0.26 percent margin.

Boysko’s petition, filed late Tuesday in Fairfax County’s Circuit Court, sets in motion a court-governed procedure to have all ballots counted again — similar to the recount underway in the election for Virginia attorney general.

Boysko’s attorney, Christian Sautter, said he expects a preliminary hearing to occur within a week.

“Given the closeness of the outcome of this race, we owe it to both candidates and to the voters to make sure that every tally is recorded correctly and every vote accounted for so the process leaves no lingering questions,” Boysko said in a statement.

A spokeswoman for Rust said that he believes he won the election but plans to honor the procedure for a recount.