House Republicans got a big break under California’s new primary system Tuesday, after Democrats failed to get a candidate into the general election for Rep. Gary Miller’s (R-Calif.) swing district.

In a Feb. 16, 2007 file photo, Rep. Gary Miller, R-Calif., is seen his office on Capitol Hill in Washington. (Dennis Cook — Associated Press)

Under the new system, the top two candidates in an open field make the general election, regardless of party. So while Miller (27 percent) and Dutton (25 percent) split up about half the vote, four Democrats on the ballot split up the other half into smaller pieces.

The result: The seat will stay Republican this fall.

It was hardly the only race where the state’s congressional delegation got a little shaken up though. The new primary system, combined with a citizen-drawn redistricting map, has put many of the state’s incumbents into tough races.

Below, we tell you who is looking vulnerable, and who had a good night.

Incumbents in trouble:

As expected, Reps. Brad Sherman (D-Calif.) and Howard Berman (D-Calif.) are headed for a November matchup. Sherman led Berman 42 percent to 32 percent in Tuesday’s vote, with mostly Republicans splitting up the rest of the vote.

Rep. Janice Hahn (D-Calif.) appears to be the clear favorite in her incumbent-versus-incumbent matchup, leading Rep. Laura Richardson (D-Calif.) 60 percent to 40 percent on Tuesday.

Rep. Jerry McNerney (D-Calif.) was under 50 percent and faces 25-year-old Ricky Gill, who has been one of the GOP’s fundraising stars so far this cycle. McNerney led Gill 48 percent to 40 percent, with another Republican earning the other 12 percent.

Rep. Brian Bilbray (R-Calif.) took just 41 percent of the vote in his new district, while the top two Democrats in the race outpolled him. It’s not yet clear whether he’ll face former San Diego City Councilman Scott Peters or former state Assemblywoman Lori Saldana, who were locked in a close race for second place.

Rep. Pete Stark (D-Calif.) took just 42 percent of the vote in his contest with prosecutor Eric Swalwell (D) and an independent candidate, meaning Stark could face a tough one-on-one matchup with Swalwell in the fall.

Rep. Jim Costa (D-Calif.) and another Democrat combined for slightly more than half the vote, but Costa got just 41 percent of it, suggesting he’s got work to do. He faces attorney Brian Whelan (R), who took 26 percent, in the fall.

A pair of Republicans outpolled Rep. Lois Capps (D-Calif.) in her newly competitive district, and the one who emerged — former lieutenant governor Abel Maldonado (R), appears to have a shot at beating her. Capps led Maldonado 46.5 percent to 30.5 percent, but Maldonado and another Republican combined for 51 percent of the vote.

Rep. Joe Baca (D-Calif.) faces a tough race with state Sen. Gloria McLeod (D). Baca led her 45 percent to 36 percent Tuesday, with a Green Party candidate taking the other 19 percent.

Open seats:

In the swingy open 26th district, GOP state Sen. Tony Strickland led the way with 44 percent of the vote and will face state Assemblywoman Julia Brownley (D), who took 27 percent. Independent Ventura County Supervisor Linda Parks (19 percent) failed to make the final ballot after some early hype.

Riverside Community College Board Trustee Mark Takano (D) will face Riverside County Supervisor John Tavaglione (R) in the Democratic-leaning 41st district. But Republicans outpolled Democrats in the district and Tavaglione led Takano 45 percent to 36 percent.

State Sen. Alan Lowenthal (D) led Republican Long Beach City Councilman Gary DeLong 34 percent to 29 percent on Tuesday in a crowded field in the Democratic-leaning 47th district.

State Assemblyman David Valadao (R) is looking like a very strong favorite after taking 57 percent of the vote in the swingy, open 21st district. He faces local Chamber of Commerce official John Hernandez (D), who split the rest of the vote with another Democrat.

Looking solid, but on the radar:

Rep. John Garamendi (D-Calif.) will face Colusa County Supervisor Kim Vann, a national GOP favorite who emerged from a field that included four Republicans. But Garamendi took 53 percent of the vote, which is a good sign for him going forward.

Rep. Dan Lungren (R-Calif.) will face a rematch with Dr. Ami Bera (D) in a top-targeted race for Democrats, but Lungren also took 53 percent of the vote.

Rep. Jeff Denham (R-Calif.) took 48 percent of the vote but outpaced his nearest competition by 20 points. Democrats got their man, though, with former astronaut Jose Hernandez making it to the general election.

Rep. Loretta Sanchez (D-Calif.) was just over 50 percent of the vote, while three Republicans combined for 45 percent. She faces Republican Jerry Hayden.

Rep. Mary Bono Mack (R-Calif.) took a very strong 58 percent of the vote in a district Democrats have talked about targeting. She faces emergency room doctor Raul Ruiz (D), who was the only other candidate in the field Tuesday.

Rep. Henry Waxman (D-Calif.) was under 46 percent of the vote in a very crowded field. He will face independent Bill Bloomfield.

Read more on PostPolitics:

New map, new rules shake up California primaries

The Fix: California’s new political reality, explained

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