SAN RAMON (CBS / AP) — The outcome in a Northern California congressional race remained too close to call Monday as counties continued to process vote-by-mail and provisional ballots.

Two-term 11th Congressional District Democratic U.S. Rep. Jerry McNerney was locked in a tight battle with Republican David Harmer, a San Ramon attorney.

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The secretary of state’s office said Monday that Harmer trailed McNerney by just 625 votes — 47.8 percent to 47.3 percent.

About 376,000 ballots were outstanding in the 11th district from San Joaquin, Santa Clara, Alameda and Contra Costa counties.

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The sprawling district extends from the East Bay into the San Joaquin Valley.

The district is reliably competitive in any election year, due to the near-even split between registered Republicans and Democrats.

The GOP and several outside conservative groups poured money into Harmer’s campaign and viewed the contest as their best hope of seizing a Democratic congressional seat in California.

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