WASHINGTON (CBSDC/AP) — Several thousand absentee and provisional ballots could affect the outcome of a close Democratic primary race for an at-large D.C. Council seat.

Incumbent Vincent Orange leads challenger Sekou Biddle by 543 votes. He has not claimed victory, and Biddle has not conceded.

The D.C. Board of Elections and Ethics says 3,348 Democrats requested absentee ballots. So far, 1,554 have been returned. Absentee ballots must be postmarked by Tuesday.

The board will also consider 3,867 provisional ballots. Elections officials are reviewing those to determine which are eligible to be counted.

All absentee and eligible provisional ballots will be counted and added to the unofficial election results on April 13. The results will be certified on April 18. A margin of less than 1 percent would trigger an automatic recount.

Some District voters said Orange’s links to a corruption scandal involving political donor Jeffrey Thompson swayed their votes.

“The platforms are largely indistinguishable,” one voter said of the two candidates. “The tipping point is the prospect of corruption.”

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