Lungren unseated by Democrat for Sacramento-area House seat
A Lungren spokesman, however, said the congressman was not conceding.
"It will be an honor to serve Sacramento County in Congress," Bera said in a written statement.
"Now is the time to find common ground and move forward to rebuild an economy that works for the middle class," he said. "Congressman Lungren deserves our appreciation for his long record of public service."
While thousands of ballots remained uncounted, Bera campaign manager Josh Wolf said that Bera has been widening his lead over Lungren since election day. On Thursday, Bera led Lungren by more than 5,000 votes.
The tight race has created an awkward situation on Capitol Hill where Bera, a physician, is attending an orientation for new House members organized by the Committee on House Administration, chaired by Lungren.
The race was among the House contests that drew the most outside money -- more than $9 million, according to the Center for Responsive Politics.
Lungren has been a political fixture in California: a former state attorney general, Republican nominee for governor and one of the few members of Congress to have represented two different districts hundreds of miles apart.
Last week's election -- following the redrawing of district boundaries by a citizens' commission instead of politicians and a spate of retirements by incumbents -- has led to the biggest shake-up of the California congressional delegation in 20 years.
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-- Richard Simon in Washington, D.C.
Photo: New U.S. Rep. Ami Bera. Credit: AP Photo / The Sacramento Bee, Lezlie Sterling