Running against the Vietnam War, Representative Pete Stark entered Congress the year Richard M. Nixon was re-elected president. Since then, ensconced in Democratic strongholds here in the Bay Area, Mr. Stark was easily re-elected 19 times. Ricky Gill, a Republican, is trying to unseat Representative Jerry McNerney, a Democrat running in a redrawn district in the Central Valley. But Mr. Stark, 80, the dean of California’s Congressional delegation, is facing a serious challenge for the first time. That is because Eric Swalwell, a fellow Democrat who became a city councilman less than two years ago in Dublin, his hometown near here, came just a few points behind Mr. Stark in the primary Now Mr. Swalwell gets to carry the fight into November — thanks to a new primary system in California under which the top two vote getters advance to the general election, regardless of party affiliation. “I wouldn’t have had a chance before,” Mr. Swalwell, 31, said before a recent afternoon and evening of campaigning.
The new primary system, coupled with California’s adoption of nonpartisan redistricting, is causing upheaval in the nation’s largest and most influential Congressional delegation. Though polls indicate that President Obama has the state locked up, some of the most competitive House races are taking place across this state, often in nontraditional form. They are pitting two members of the same party against each other in seven other districts. In two of those, two Democratic incumbents are facing off, most notably Representatives Howard L. Berman and Brad Sherman, both influential veterans, who have spent millions of dollars in a battle for a seat in the San Fernando Valley.