Orange County primary results still being tallied

SANTA ANA, Calif. (KABC) -- There are tens of thousands of ballots still to be counted at the Orange County Registrar of Voters in Santa Ana following Tuesday's California primary election.

That doesn't include the thousands of ballots dropped in the mail, which officials say will require patience from candidates in tight races such as the 48th congressional district.

Incumbent Republican Dana Rohrabache will move on to November, but the second-place challenger remains unclear. Businessman Harley Rouda leads stem cell scientist Dr. Hans Keirstead by less than 100 votes as of Wednesday evening. Both are Democrats.

The large field of candidates worried Democrats that they could split the vote, allowing two Republicans through to November.

In California's primary system, the top two vote-getters move on, regardless of party.

Republican Mimi Walters, the incumbent representing the 45th district, will face UC Irvine professor and Democrat Katie Porter.

In the 39th district, where Republican Ed Royce is not seeking reelection, Republican and former state assemblywoman Young Kim is leading Democrat Gil Cisneros, a veteran and lotto millionaire.

In the 49th district, represented by retiring Republican Darrell Issa, Republican and California's Board of Equalization Chair Diane Harkey heads to November.

Democrats Mike Levin and Sara Jacobs trailed Harkey as of Wednesday night.