Data from the 2020 census were released Thursday, kicking off efforts to reshape House districts ahead of the 2022 midterm elections. The data showed which counties, cities and neighborhoods gained or lost the most people since the 2010 census.

The data showed there is now no majority racial or ethnic group for people younger than 18. The share of non-Hispanic whites in the age group dropped from 53.5 percent to 47.3 percent over the decade. The Asian and Hispanic populations exploded from 2010 to 2020, increasing by around a third and almost a quarter respectively over the decade.

Some demographers cautioned that the white population was not shrinking, shifting to multiracial identities. The number of people who identified as belonging to two or more races more than tripled between 2010 and 2020. They now account for 10 percent of the U.S. population.

The new data also found the child population has actually decreased since 2010, due to falling birth rates. Overall, the U.S. saw its slowest population growth since the Great Depression.

Based on the data, lines will be redrawn for 429 U.S. House districts in 44 states, and 7,383 state districts across the U.S. While the official goal is to ensure each district has roughly the same number of people, Republicans and Democrats will look to gerrymander those district lines in order to give their candidates the best chance to win future elections.

As they did after the 2010 census, Republicans will hold greater sway in the redistricting process this year.

The GOP will control redistricting in 20 states, accounting for 187 U.S. House seats. Democrats will control redistricting in just eight states accounting for 75 seats.

In 16 other states, districts will be drawn either by independent commissions or by state politicians with legislative chambers led by one party and governors of the other. Those 16 states account for 167 House seats.

Six states have just one House seat, so there are no district lines to be drawn.

This round of redistricting is especially important considering how slim the Democrat majority is. Republicans need to gain just five seats to take control of the House in 2022. Experts say that’s a margin that could be covered through redistricting alone.

“Redistricting really is the ballgame this cycle in the House,” said David Wasserman, an analyst at The Cook Political Report. “Even tiny changes to district lines could have huge implications that tip the balance of power in the House.”

This year’s redistricting process will have a shorter timeline than usual. States are getting the data more than four months later than normal due to difficulties in conducting the census during the pandemic. Map-drawers will have to work quickly to meet constitutional deadlines in some states or seek judicial approval to take longer.  For example, in Ohio, there is a Sept. 15 deadline for the redistricting board to approve new state legislative maps.

“We’re in a bit of a fix over how quickly we can get this done,” said Ohio Senate President Matt Huffman, a member of the board.