State Sen. Juan Vargas has a commanding lead after early returns to replace Congressman Bob Filner in the 51st congressional district and is within striking distance of winning the seat outright.
The longtime Democratic state legislator has 47.5 percent of the vote after the San Diego Registrar released a count of early absentee ballots.
Republican Michael Crimmins has 21.1 percent of the ballots returned and Democrat Denise Ducheny has 13.8 percent.
The border district, which also includes all of Imperial County, had 20,457 total votes submitted with 19.8 percent of precincts reporting when the registrar released the votes shortly after polling places closed at 8 p.m.
Unless one of the candidates gets more than 50 percent of the vote, the top two finshers will proceed to a November runoff.