SACRAMENTO (AP) — Democratic Rep. Jerry McNerney has been re-elected to a third term in a Northern California congressional district, fending off a challenge from Republican David Harmer.

McNerney held a lead of nearly 2,500 votes on Wednesday with less than 1,900 ballots left to be counted.

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His re-election means no California congressional seat changed party hands, even as Republicans took back the U.S. House of Representatives with a national GOP landslide on Nov. 2.

“Congressman McNerney is honored to be re-elected to the 11th congressional district,” spokeswoman Sarah Hersh said. “He looks forward to the opportunity to serve the people of this area, to work to create jobs and to work to improve benefits for veterans.”

Harmer sent a message to supporters Wednesday afternoon saying that it appeared unlikely he would overcome the deficit. But he refused to concede.

“Every legitimate vote should be accurately counted,” Harmer wrote. “Having waited three weeks for partial results, we can wait one more week for final numbers.”

Republican National Committee Chairman Michael Steele had campaigned for Harmer in trying to rally conservatives to block President Barack Obama’s agenda. It was Harmer’s second run for Congress in California.

In 2009, the former corporate lawyer lost to then-Lt. Gov. John Garamendi in a special election for the 10th Congressional District, where Democrats hold an 18-point registration edge.

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The 11th District won by McNerney covers four counties stretching from the Bay Area to a region of the Central Valley that includes Lodi and part of Stockton. It is evenly split between registered Democrats and Republicans, with independents comprising 18 percent of voters.

McNerney’s victory follows a win by Rep. Jim Costa, another Central Valley Democrat who found himself in a tight race this year.

Costa, a conservative Democrat, beat Republican Andy Vidak, a farmer running for his first political office, in the 20th Congressional District. With just a small number of ballots outstanding, Costa had a lead of 51.7 percent to 48.2 percent.

Costa and McNerney will return to a much different Congress next year, with Republicans in charge of one house and vowing to block the president’s initiatives.

In 2006, McNerney unseated incumbent Republican Rep. Richard Pombo in a district that leaned slightly Republican at the time. A wind-energy engineer with a doctorate in math, McNerney has played a role in alternative energy legislation and sits on the House Transportation and Infrastructure Committee.

Hersh said McNerney has always made bipartisanship a part of his tenure and “will work across party aisles to serve the people he represents well.”

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