California's bipartisan Citizens Redistricting Commission officially approved the state's redrawn congressional map late Thursday, triggering a spate of announcements for candidates running in districts that are very different from their old ones.

Rep. Janice Hahn (D), who just won a special election in a coastal Los Angeles district, announced she will run in a newly created, heavily African-American and Hispanic district in South Central Los Angeles. Hahn, who is white, will face African-American Rep. Laura Richardson (D) and Assemblyman Isadore Hall, who is also African-American.

Los Angeles City Councilman Tony Cardenas, a Hispanic Democrat, also announced for Congress Monday. He will run for a newly created Hispanic-majority district in the San Fernando Valley in northern Los Angeles.

Another candidate that announced in recent days is former Assemblywoman Lori Saldana (D), who plans to challenge Republican Rep. Brian Bilbray in a Republican-leaning San Diego district.

Many incumbents face uncertain futures in the state. Republican Reps. David Dreier, Elton Gallegly, Ed Royce, Gary Miller and Dan Lungren are all at risk because of the new map, as are Democratic Reps. Lois Capps, Howard Berman and Brad Sherman. Berman and Sherman are likely to face off against each other, and Royce and Miller may as well.

Rep. Bob Filner (D) has already announced a run for San Diego mayor rather than trying to win a heavily Hispanic San Diego-area district, while Rep. Dennis Cardoza (D) is mullling retirement.