From Michael Doyle in Washington, D. C.
California's congressional delegation will remain the same size while Texas and Florida will bulk up, under final 2010 census results released Tuesday morning.
California will retain its current 53 House seats for the coming decade. Along with every other state, California will also keep two senators.
Reapportionment following the 2010 census still leaves California with the largest delegation in the 435-member House of Representatives. As the nation's population grew 9.7 percent to 308,745,538 though, the overall balance shifted across the country.
"This is really an important day for the American people," Commerce Secretary Gary Locke said at the National Press Club. "Much is riding on the results."
All told, 18 states will either gain or lose House seats, while 32 states will stay the same
The 2010 census marks the first time since 1920 that California has not gained at least one House seat following a census. No House seats were reapportioned for any state following the 1920 census. More broadly, it marks a continued population tilt away from Rust Belt states into the Sun Belt.
The new population count, for instance, will increase the Texas congressional delegation to 36, up from the current 32. That will almost certainly boost House Republicans after the 2012 election, as the GOP already controls the state legislature in the heavily Republican state.
Florida will now have 27 seats, up from the current 25. As in Texas, Republicans control the Florida legislature that will draw the new House district lines.
"We see a continuation of a decades-long growth in the southern regions," Census Bureau Director Robert Groves said.
Still, Democrats insist they aren't concerned about a reapportionment that by some estimates could put an additional 10 House seats into the Republican roster.
"It's a little bit like worrying about the weather," White House spokesman Robert Gibbs said. "I don't think that shifting some seats from one area of the country to another necessarily marks a concern that you can't make a politically potent argument in those new places."
The California residents counted as of April 1, 2010 include citizens, non-citizens and illegal immigrants, as well as military personnel temporarily stationed overseas.
In 2000, California's population was 33.8 million. That had increased enough since the 1990 head-count to earn the state one additional House seat. In the redistricting that followed, the southern San Joaquin Valley gained the new 21st Congressional District that includes all or part of Fresno, Kings and Kern counties.
Following the 1990 census, California had gained a whopping seven House seats.
The census figures released Tuesday do not include all of the in-state population details that will be used in the drawing of California's new congressional districts. That work will be done next year by a new 14-member Citizens Redistricting Commission.
Each new House district will include an average of 710,767 residents.
Previous studies by the non-partisan Rose Institute of State and Local Government have suggested that California's population shifts could move all or part of one additional House district into the San Joaquin Valley.
"None of us have a clue, frankly, what the districts are going to look like," said Rep. Jim Costa, D-Fresno.
Beyond redistricting, the new population numbers will be used to help divvy up federal dollars. California currently receives more than $41 billion in federal funds that are driven by the population count, state officials estimate.
More information on the state and national population totals and the apportionment breakdown, including interactive maps and historical data, is posted on the U.S. Census Bureau website.
Editor's note: This post was updated at 11 a.m. to correct California's reapportionment history.