Democrats hold every statewide office in California and the two U.S. Senate seats and have majorities in both houses of the Legislature. They also hold a registration edge of 2.2 million voters over Republicans, and independents outnumber Republicans in about a dozen congressional districts.
The Legislature's gerrymander of legislative and congressional districts after the 1990 census cemented Democratic control of the Assembly and Senate while protecting incumbents of both parties.
Between 2000 and 2010, just one House seat changed party hands, when Rep. Jerry McNerney won a seat in the agriculture-heavy Central Valley from former GOP Rep. Richard Pombo.
Now even the contours of McNerney's district have changed, and he faces a tough campaign against Republican challenger Ricky Gill, a 25-year-old law school graduate whom national Republicans consider one of their top hopes for defeating a Democratic incumbent.
Gill, who netted a short speaking slot at the Republican National Convention in Tampa, Fla., has snagged endorsements from former Florida Gov. Jeb Bush and South Carolina Gov. Nikki Haley. He also has proved an effective fundraiser, bringing in nearly $1.8 million in campaign cash, some of it thanks to his parents' connections in California's growing Indian-American community. McNerney has raised about $1.5 million.
Their race for the 9th Congressional District is partly within the Sacramento television market, which is commanding much of the spending this year because it touches numerous competitive districts.
One of those is the seat now held by Republican Rep. Dan Lungren, a former state attorney general who faces a Democratic challenger, physician Ami Bera, whom he barely defeated two years ago.
Another is the race involving incumbent Democratic Rep. John Garamendi, who is competing in a much less favorable district than the one that elected him. His opponent, Republican Kim Vann, is a member of a farming and ranching family stretching back four generations in the heart of the new district, north of Sacramento.
Vann said Garamendi still behaves as if he were trying to win over progressive voters in his old San Francisco Bay area district rather than reaching out to families in rural Colusa County.
"This is my home. I'm not running around looking for a seat to shop," she said. "All you have to do is look at his voting record and look at the needs of the people in this district, and they don't match up."
Garamendi, who has held state and federal political offices for nearly four decades, said he was confident voters recognized his service to the area. He said Vann is relying on "shadowy" super PACs to fund a flurry of negative TV ads against him.
"In a normal campaign, you would be looking at a million-dollar congressional race," Garamendi said. "But with what amounts to unlimited funding, they are buying up television time starting in August. And a million-dollar television buy in Sacramento means you're basically on every commercial break."
In Southern California, Democratic-leaning super PACs have spent about $750,000 to support state Assemblywoman Julia Brownley, who faces a tight race against Republican state Sen. Tony Strickland in the 26th District along the Ventura County coastline. Democrats have just a 4 percentage point advantage.
Democratic incumbent Rep. Lois Capps is facing the toughest race of her political career in a newly drawn district along California's central coast that includes Santa Barbara and San Luis Obispo. Former state Sen. Abel Maldonado, a wealthy farmer, is mounting a spirited challenge in a district that is nearly evenly divided between Democrats and Republicans.
Independents account for about 1 in 5 voters in both of those districts and are seen as key for each of the campaigns.
Having such a large number of congressional districts in play has attracted far more money to California than in years past.