New census data shows declining populations in rural areas and some Rust Belt cities, which could make them targets during redistricting for the U.S. House.

State politicians and commissions must redraw U.S. House districts before the 2022 elections to account for population shifts toward big cities and suburbs.

That means that some districts that lost residents will need to be eliminated or expanded geographically to take in more people. Rural areas in Illinois, Michigan, Ohio and Pennsylvania showed population losses, as did some of their cities. Republicans and Democrats will be battling over which districts must be eliminated.