Census data shows U.S. growing more diverse as congressional redistricting fights loom

The Census Bureau released its most detailed look so far detailing the results of the 2020 census on Thursday afternoon, kickstarting what is expected to be a highly contentious battle as states begin redrawing the boundaries of congressional districts.

The data includes a breakdown of demographic categories like race, Hispanic origin and age, down to a neighborhood block. The bureau also posted demographic data for every city with over 5,000 residents, showing the nation has grown more diverse over the past decade.

White residents remain the largest racial group in the U.S., with 204.3 million people, but their numbers declined over the past decade, falling by 8.6%. 

Hispanic or Latino residents were the second largest group in the country, comprising 18.7% of the total population. They were also the second most prevalent group in a significant amount of counties. In Texas, a state that will be adding two Congressional seats, Hispanic or Latino residents closed their gap with White residents to less than half a percentage point.

The multiracial population saw a huge spike as well, going from 9 million in 2010 to 33.8 million in 2020.

"Our analysis of the 2020 Census results show that the U.S. population is much more multiracial, and more racially and ethnically diverse than what we have measured in the past," Nicolas Jones, a Census Bureau director in the population division, said on Thursday.

The adult population also grew faster than the nation as a whole, with 258.3 million people over the age of 18, a 10.1% increase since 2010.

A majority of the population growth occurred in cities and suburban areas, as 86.3% of the country now resides in "urban core" counties or those with 50,000 residents or more. The 10 largest cities remained the same, though Phoenix overtook Philadelphia as the fifth most populous. The 10 fastest growing cities in the country were all in southwestern states, with Buckeye, Arizona, a city near Phoenix, seeing a population growth of 80%.

The population figures and the block-by-block breakdown are needed for commissions and state legislatures to begin their once-in-a-decade process of redistricting: redrawing the boundaries of everything from congressional and legislative districts to city wards. In April, the Census Bureau unveiled the number of congressional seats each state will receive based on the decennial population count.

Thursday's release serves as the starting pistol for the process. The data itself was released in a complicated, non-user-friendly format, and redistricting groups expect that commissions and state legislatures will need weeks to sort out and convert the data before they start redrawing maps.

A more user-friendly version of this data is slated to come out September 30. One vendor described Thursday's data release as the "IKEA furniture" version: officials will have all the pieces, but will have to put it together themselves.

The urgency to get started on redistricting stems from delays in census data collection and each state's constitutional deadlines for redistricting and candidate filing. Some states such as California, Texas and Illinois have pushed or are looking at pushing their deadlines back. Democratic and Republican groups expect at least 25 to 35 states will be done with their maps by the end of this year.

Some states like Colorado and Virginia have started holding public redistricting hearings or have released preliminary maps in order to get ahead of the process and meet their deadlines. Thursday's data will help them craft their official maps. 

With Democrats holding onto a slim majority in the House, redistricting will have huge ramifications for determining which party controls the lower chamber after the 2022 midterm elections.

Texas, North Carolina and Florida have Republican legislatures in control of redistricting, and each state will add at least one congressional seat. Both Democrats and Republicans believe these legislatures will try to "gerrymander," or draw lines in their political favor, enough districts to flip control of the House. 

Kelly Ward Burton, executive director of the National Democratic Redistricting Committee, wrote on Thursday that the group believes Republicans can draw 11 to 16 more seats in their favor in Texas, North Carolina, Florida and Georgia alone.

Democrats are also in control of drawing seats or have final approval on maps in historically gerrymandered states like Illinois, Maryland and New York. 

Thursday's data release also impacts congressional and legislative candidates, who have been in limbo regarding where they are actually running due to the delay in map drawing. In his campaign launch, Texas Republican candidate Wesley Hunt wrote that he will announce the district he'll run in "as soon as Texas releases their newly redrawn Congressional district lines."

As part of a larger battle over voting rights, congressional Democrats have been pushing for passage of the For The People Act, which would mandate every state establish an independent commission for drawing congressional district lines. The bill has stalled in the Senate.