With 100 percent of precincts reporting, Democrat State Senator Juan Vargas and Republican Michael Crimmins will face off to determine who represents IB and the 51st Congressional District in Washington.
Vargas currently represents the 40th Senate District which includes Chula Vista, South San Diego and Imperial County.
Republican Michael Crimmins ran for the 53rd District against Congresswoman Susan Davis in 2008 and 2010.
Under California's new "top-two'' primary system, the pair of candidates with the most votes will square off in the general election in the House races.
That second spot in the had been expected to go to former Sen. Denise Moreno Ducheny, D-San Diego, who instead finished third.
Juan Vargas 21,201 45.7 Michael Crimmins 9.429 20.3 Denise Moreno Ducheny 7,179 15.5 Xanthi Gionis 3,123 6.7 John Brooks
2,356 5.1 Daniel Ramirez 1,884 4.1 Bernard Portley
Following redrawn lines determined by the California Citizens Redistricting Commission, Imperial Beach will leave California's 53rd Congressional District and join the 51st District following elections in November.
The 51st will now span the entirety of the California-Mexico border, from IB to Arizona.
The 53rd had been represented by Democrat Bob Filner for two decades who gave up his seat to run for mayor. He finished second in Tuesday's mayoral primary.
City News Service contributed to this report.