For the second year in a row, the U.S. Census Bureau is estimating Illinois’ population decreased, a trend that could lead to the state losing a congressional seat.

In U.S. Census Bureau estimates released last month, Illinois’ population decreased by 22,000 people from 2014 to 2015. Because of the estimated drop, Election Data Services, a Virginia-based political consulting firm, projects Illinois will lose a representative in the U.S. House of Representatives.

The census bureau uses birth and death certificates, as well as address changes on tax returns to estimate population between the decennial population counts.

Illinois is one of nine states that could lose a representative in Congress. According to Election Data Services, Alabama, Michigan, Minnesota, New York, Ohio, Pennsylvania, Rhode Island and West Virginia also could lose a seat.

Arizona, Colorado, North Carolina and Oregon would each gain one seat, Florida would gain two seats, and Texas might gain three seats under the Election Data Services projections.

Kimball Brace, president of Election Data Services, reiterated the projections are only preliminary, and how many congressional seats each state will have won’t be finalized until the 2020 census is completed.

“We are only at the midpoint of the decade, and a lot of things could change before the next census is taken in 2020,” Brace said. “Having worked with census data and estimates since the 1970s, it’s important to remember that major events like Katrina and the 2008 recession each changed population growth patterns and that impacted and changed the next apportionment.”

Illinois’ current delegation in the U.S. House of Representatives has 10 Democrats and eight Republicans. Five of the Republicans represent areas outside of Chicago, and three are in the collar counties of Chicago. Nine of the Democrats represent Chicago-area districts, and one represents northwestern Illinois, including the Quad Cities area.

Congressional lines are drawn by the state legislature, and are subject to the governor’s approval. That means the 2018 and 2020 elections will be important, especially if the governorship is held by a Republican and the legislature is controlled by Democrats, or vice versa.

“That’s where all bets are off,” said Ken Moffett, an associate professor of political science at Southern Illinois University-Edwardsville. “You can have any number of alignments coming out of there.”

He added what could end up happening in a divided government situation is mostly incumbents being protected.

“What tends to happen is the partisanship tends not to change that much,” Moffett said. “A district that remains, and leans one way or another, tends to be driven stronger in that direction. The other way this sometimes happens is you cut out a district with a person who is retiring and carve it out that way.”

Moffett said which party has control of the legislature and governorship in the state will be key to determining congressional lines.

“If it’s all Democratic control, then the goal will be to maximize the number of Democratic representatives,” Moffett said. “My guess in that case … you’ll have a Republican losing a seat, or gerrymandered into another district where they face off against another Republican.”

After the 2010 Census, Illinois’ maps were re-drawn and pushed Republican Rep. Randy Hultgren and former Republican Rep. Joe Walsh into the same district in the Chicago suburbs. Walsh eventually decided to run in another district, but lost to Democrat Tammy Duckworth.

In 2002, after the 2000 realignment, Democratic incumbent David Phelps of Eldorado and Republican incumbent John Shimkus of Collinsville faced off in a newly formed 19th district. Shimkus won in the predominantly Republican district.

Shimkus said of the 2021 redistricting process that “the lines could be anywhere. Everything is possible. It depends on the members who are there.”

If Republicans were able to gain control of the state legislature, Moffett says they possibly would draw the map in a way to pick off a Democratic seat in the Chicago area.

David Yepsen, director of the Paul Simon Public Policy Institute at SIU, said he believes if the population trends hold up, and Illinois does lose a congressional seat, lawmakers could eliminate a seat in the rural parts of the state, anywhere outside of the Chicago-area.

“Rural America is losing population,” Yepsen said. “The Rust Belt is losing population to the south.”

“It’s not easy to say where it could come from,” Yepsen added. “It could resolve in all the rural districts getting larger.”

Losing a congressional seat also would mean the state would lose an electoral vote in presidential elections, which could have a factor in the electoral balance.

Illinois, typically a safe Democratic state in presidential elections, could end up losing an electoral vote to a Republican-leaning state or a battleground state, Yepsen said.

“It does change the mix in the Electoral College,” Yepsen said.

Besides the Electoral College, having one less representative reduces the clout of the state in Congress, Yepsen said. As Midwest and New England states lose population, committee assignments in Congress move to the South and West.

John Jackson, a visiting professor at the Paul Simon Public Policy Institute, said he would expect downstate districts to need to get geographically larger, along with districts within the city of Chicago, to accommodate a potential congressional seat loss.

“Even if the city [of Chicago] takes a hit, Bost’s district has to get geographically bigger, Shimkus’ has to get bigger,” Jackson added.

Jackson said Chicago Democrats were able to protect themselves in the last redistricting, which included Illinois losing a district, by having districts that reached out into the suburbs.

However, population in the collar-county area of Chicago has grown and districts may not need to be changed all too much.

“What’s not vulnerable is the collar counties, they’ve done quite well,” Jackson said.

The average population in each district was 710,000 people, according to the Census bureau. Jackson estimates the average population will be about 800,000 after the redistricting.

“Nothing is absolute or set in stone,” Jackson said. “Things can change. We were fairly close to the bubble last time … If something significant stops our slide or reverses our slide, again we’ll be back on the bubble.”

Congressional district rules

— Districts have to contain an equal amount of people.

— Districts can’t be drawn to overly discriminate toward members of a racial minority. Race also can’t be the predominant factor in a district’s design. It can be one of several factors.

— A congressional district has to be contiguous.

According to Census estimates

— Since 2010, Illinois has grown by 28,446 people. The U.S. average is 248,249 people per state.

— Illinois grew by .2 percent, but the entire country had a 4.1 percent growth since 2010.

— Illinois is leading the country in net migration losses. The state has a net migration loss of 255,000 people since 2010.

Number of congressional districts in Illinois

— Current: 18 districts

— Last decade: 19 districts

— 1990s: 20 districts

— 1980s: 22 districts

— 1970s: 24 districts

— 1960s: 24 districts

(c) 2016 the Belleville News-Democrat (Belleville, Ill.)

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