LOS ANGELES -- Los Angeles City Councilwoman Janice Hahn advanced to a runoff in the election to fill Democratic Rep. Jane Harman's Southern California congressional seat, but the race for second place was too close to determine who her opponent would be.

With all precincts reporting, Hahn, a Democrat, led the other 15 candidates in Tuesday's election with 24.6 percent of the vote.

Republican businessman Craig Huey, 60, who has tea party support and lent his campaign $500,000, had 21.8 percent, and California Secretary of State Debra Bowen, a Democrat, had 21.4 percent. Only 206 votes separated Huey and Bowen early Wednesday, and there were 9,811 mail-in, provisional and damaged ballots yet to be counted, said Marcia Ventura, spokeswoman for the Los Angeles County registrar-recorder.

The count was scheduled to be completed Friday, Ventura said. The top two finishers will face each other in a July 12 runoff.

Huey's campaign manager, Jimmy Camp, said he was confident Huey's lead would hold and he wasn't surprised by the conservative Republican's strong showing in a heavily Democratic district that stretches from the famous Venice boardwalk through the playground of Manhattan Beach to the edge of the sprawling Los Angeles port.

"It's what we've seen all along," Camp said. He credited campaign volunteers with getting voters to the polls on Election Day.

Bowen's campaign was also confident that she would be in the runoff.

"We know that with 9,811 ballots yet to be processed that's more than enough to make up the difference," Bowen campaign spokesman Luis Vizcaino said.

Hahn, 59, scion of a prominent Los Angeles political family, emerged as the establishment favorite, winning endorsements from U.S. Sen. Dianne Feinstein, D-Calif., Los Angeles Mayor Antonio Villaraigosa and the powerful Los Angeles County Federation of Labor. Bowen, a 55-year-old former legislator, had the backing of the Sierra Club, the California Nurses Association and former Democratic National Committee Chairman Howard Dean.

The field consisted of five Democrats, six Republicans, a Libertarian, one Peace and Freedom candidate, and three candidates with no party affiliation.

The race also was notable because it was the first congressional test of California's new open primary system for electing lawmakers. Voters, regardless of registration, could select candidates from any party. If no one receives a majority, the top two vote-getters advance to a runoff, even if they are from the same party.

Harman, who built a reputation as a moderate, resigned in February to head the nonpartisan Woodrow Wilson International Center for Scholars, a Washington, D.C.-based think tank. She served eight terms representing the 36th District and was a leading voice for Democrats on intelligence and security issues.

Harman assumed her late husband's seat on the board of Newsweek Daily Beast Co. after his death last month at the age of 92. Sidney Harman bought Newsweek for $1 from The Washington Post Co. last fall and merged it into a joint venture with Barry Diller's IAC/InterActiveCorp, the parent of the Daily Beast.