Minnesota is facing the risk of losing one of its congressional seats after the next census amid booming population gains elsewhere in the country, a rare event that could diminish the state’s voice in Washington.

It’s been half a century since Minnesota last lost a congressional seat, and more than a century since it had fewer than eight representatives in the U.S. House. But despite outpacing the rest of the Midwest in population gains since 2010, Minnesota’s growth has been overshadowed by massive shifts in places like Texas and Florida.

Similar fears of losing a seat preceded the 2010 census, when Minnesota ultimately retained to its eighth seat by just a couple of thousand people. A lot could change before the 2020 census, which determines how the seats are distributed, but state demographer Susan Brower said Minnesota appears more at risk than last time. Most national analyses are forecasting that Minnesota will drop a seat based on current population trends.

“It’s not certain, but it looks serious and it looks like it’s maybe even likely,” Brower said.

That will mean divvying up the state into seven logical slices rather than eight during redistricting, which occurs every 10 years. And at least one member of the delegation would have to pack his or her bags in 2022.

It sets the stage for a particularly contentious fight over drawing the lines, potentially attracting more out-of-state interest in state elections in 2018 and 2020 — including next year’s governor’s race. The Legislature has authority over redistricting, subject to veto from the governor, though the courts have had to make the final maps for several decades.

“That adds a whole new level of partisan intensity to the elections that might affect the reapportionment,” said Steven Schier, a political science professor at Carleton College.

Losing a seat would also knock down the state’s clout in the Electoral College since the electors are tied to the number of representatives in Congress.

There are further concerns about the census itself, which will for the first time rely heavily on existing data to gather addresses and the internet to handle responses — rather than canvassing and responses by mail. The Government Accountability Office recently labeled the 2020 census “high risk” due to lack of preparedness for using the new techniques.

Bob Tracy of the Minnesota Council on Foundations, which is helping lead a partnership gearing up for the census, highlighted the need to be prepared.

“The census is the largest mobilization we do as a country besides going to war,” Tracy said. “If we’re not doing development and testing, it could be really ugly come April 1st, 2020.”

Bigger in Texas

Minnesota has added about 216,000 people since 2010, based on the latest estimates from the Census Bureau, a growth rate of about 4 percent. Most of it was due to births outpacing deaths and international migration rather than domestic migration. About 85 percent of the state’s growth was in the seven-county metro area.

Texas, Florida and California, by comparison, have all grown by more than a million people. Florida and Texas are each expected to pick up a couple of congressional seats, based on an analysis by Virginia-based Election Data Services, a consulting firm that tracks the issue. States the group expects to lose a seat are largely Midwestern and Northeastern, including Minnesota, Illinois, Michigan, New York, Ohio, Pennsylvania, Rhode Island, Alabama and West Virginia.

The distribution of congressional seats is calculated by balancing each state’s population relative to others. Kimball Brace of Election Data Services said Minnesota’s closest competition to keep its eighth seat is likely Montana, which is projected to possibly pick up an extra seat by a slim margin.

Nonetheless, Brower said, “We’re growing really well, actually, as compared to our neighbors.”

If Minnesota loses a seat, it’s likely to result in larger districts with a wider variety of constituents.

“As districts get larger, you have a more diverse population, which makes it more challenging in Congress to meet all the needs of your constituents,” said Rep. Sarah Anderson, R-Plymouth, who chaired the House redistricting committee in 2012. The goal is to keep communities of interest together, she said.

Former DFL congressman Tim Penny said having three largely rural districts, two for the central cities and three for suburban and exurban areas has been a logical way of carving up the state. That would be lost with one fewer seat, he said, and may result in broader rural districts with less cohesion.

“There’s no denying that it diminishes the rural voice. And that is concerning,” said Penny, now president of the Southern Minnesota Initiative Foundation.

Congressman Collin Peterson’s rural district on the state’s western edge is already so large that he pilots a Beechcraft Bonanza plane to get around. Now the dean of Minnesota’s delegation after 26 years in Congress, Peterson, a Democrat, is concerned about a shake-up diminishing the seniority of the state’s delegation.

“If losing a seat and reapportioning the districts causes complete upheaval so we’ve got all freshman congresspeople, that is going to significantly alter what we’re able to accomplish for Minnesota,” Peterson said.

Preparing to count

Redistricting has already captured some attention at the State Capitol this year. The House and Senate have passed GOP-backed bills that would enshrine principles of redistricting into state law, such as not drawing lines to protect or oust incumbents and not diluting minority voting strength.

But first Minnesota needs to find out how many people live here and how many congressional seats the state gets.

Minnesota had the second-highest participation rate in the 2010 census, after Wisconsin.

Tracy, of the Council on Foundations, said that was in part because of the public and private money invested in outreach. His group is pushing for additional funding for the demographer’s office in the next budget to help staffers prepare.

“What we need now is that Minnesota-specific initiative to get to those communities that we know are at high risk” of being undercounted, Tracy said.

Brower added that the estimates leading up to the census aren’t perfect.

“That’s why I still have some hope and some sense that we need to still be doing everything that we can be doing to produce a good count here,” Brower said. “Because I know those numbers are just estimates.”

Eric Roper • 612-673-1732

Twitter: @StribRoper