WASHINGTON – Colleagues become competitors and political hometowns get unsettled under a proposed new congressional district map unveiled Friday.

"There's going to be a fair amount of entertainment, in terms of competitive races," predicted UC Berkeley political scientist Bruce Cain.

Until now, scandal-free House incumbents have essentially been guaranteed re-election thanks to gerrymandering. But under the proposed House map, Cain calculated that between "one third to one-fourth" of California's 53 House seats could realistically pit Republicans against Democrats.

Some veterans, like Rep. David Dreier, R-San Dimas, are thrown into a new district dominated by voters from the other party. Some, like Rep. Jerry McNerney, D-Pleasanton, could face running against one of their own party.

Overall, Democrats appear the winner, potentially adding several House seats.

"It appears to give Democrats even greater strength," acknowledged Rep. Dan Lungren, R-Gold River.

The competition could still shift, though, as the public weighs in and the California Citizens Redistricting Commission prepares final maps by August.

"This is only the opening salvo of this thing," cautioned Rep. Dennis Cardoza, D-Atwater.

Some California congressional incumbents can settle in to comfortably familiar districts. A prime example is Rep. Doris Matsui, D-Sacramento, whose district remains consolidated around the capital and immediate surroundings.

Some, like Rep. John Garamendi, D-Walnut Grove, would shift more but still retain a safe seat. Garamendi's potential new district spanning Yolo and Solano counties also has the advantage, unlike his current district, of including his actual home.

"I represented this area before as a state official, so none of the area is new to me," Garamendi said.

Other re-election-seekers could have more work cut out for them. Lungren's new district, for instance, encompasses Sacramento County outside of the city of Sacramento. The voter registration is roughly even, making it a competitive district.

"I've always taken the district I've gotten," Lungren said.

Natalie LeBlanc, an adviser to Democrat Ami Bera, who challenged Lungren last November, said Bera's camp is thrilled with the makeup of the draft district. The Elk Grove physician is planning another run against Lungren, even though Bera would live outside the district under the new map.

Another kind of competition could turn same-party colleagues against one another. Once the maps are final, expect lots of maneuvering to claim the best seat.

McNerney, for one, currently lives in Pleasanton while representing a district that contains portions of San Joaquin County that include Tracy and Manteca. The proposed map turns Pleasanton and the larger Livermore Valley over to another district centered in the East Bay.

This new map seemingly presents McNerney with a stark choice. If he wants to keep his Pleasanton base, he must either chase off or challenge 79-year-old Rep. Pete Stark, D-Fremont. Or, McNerney could shift his attention to a Stockton-centered district which is safely Democratic but also outside of his current home.

"Once the final maps are produced, he'll move forward from there," McNerney's spokeswoman Sarah Hersh said Friday.

Geographically, one of the state's biggest stretches involves the Sierra Nevada.

Currently, Rep. Tom McClintock, R-Elk Grove, represents the 4th Congressional District that runs from Roseville north to the Oregon border. The new map essentially reverses direction, running from Roseville mostly south through Tuolumne and Mariposa counties into mountainous eastern Fresno County.

The proposed foothill district is undeniably conservative, though the severance from larger cities bothers some.

"It's sheer lunacy to cut the mountains out from the places where people go to do their shopping, in Fresno or Visalia," said Rep. Devin Nunes, R-Tulare.

Bay Area districts are mostly only tinkered with, keeping the region's uniformly Democratic delegation safe. In some prominent cases, like the San Francisco seat securely held by House Minority Leader Nancy Pelosi, the concentrated urban population assured retention of similar district boundaries.

AT A GLANCE

Here are some highlights of the draft district maps for the Sacramento region released by the California Citizens Redistricting Commission.

CONGRESS:

• GOP Rep. Dan Lungren of Gold River would find himself in a more compact and less Republican district.

• The district of Rep. John Garamendi, D-Walnut Grove, would also contract, and would take Yolo County areas now represented by Democrat Mike Thompson. Garamendi's district would remain Democratic.

• The proposed district of Rep. Doris Matsui, D-Sacramento, remains consolidated around the city of Sacramento but would stretch across the river to West Sacramento.

• The Placer County-based district of Rep. Tom McClintock, R-Elk Grove, remains reliably Republican. But instead of reaching north to the Oregon border like the current district, it would curl south along the foothills nearly to Fresno.

• The district of Rep. Wally Herger, R-Chico, would pick up much of the northeast state from McClintock's district, and include Nevada City.

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Call Michael Doyle, Bee Washington Bureau, (202) 383-0006. Torey Van Oot of The Bee Capitol Bureau contributed to this report.

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