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Minnesota may have avoided losing a congressional seat after the 2020 census because of an overcounting of state residents.

The once-a-decade headcount that is used to allocate political power and federal funding may have overcounted Minnesota's residents by 219,000 people, or 3.8% of the population, according to results released Thursday from the U.S. Census Bureau's study of its accuracy.

The overcount "might have helped us" save the congressional seat, said state demographer Susan Brower. "But there are thousands of other things that could've happened as well."

After new population totals were released in early 2021, Minnesota was allocated the 435th and final congressional seat in the House of Representatives; if Minnesota had counted 26 fewer people, that seat would have gone to New York. That state's population was also overestimated, and by an even larger margin.

The figures released Thursday from the Post-Enumeration Survey serve as a report card on how well residents in the 50 states and District of Columbia were counted during a census that faced unprecedented obstacles due to the pandemic, hurricanes and wildfires, social unrest and interference by President Donald Trump's administration.

The integrity of the headcount was a source of contention even before the census was underway, and the U.S. Supreme Court ultimately sided with the Trump administration to halt the census in October 2020, over the objection of those who said it would leave many people uncounted.

The new survey reinterviewed a sample of residents and compares those results to the census to see "what we did right and what we did wrong," said Census Bureau official Timothy Kennel.

Unlike in 2010, the survey found numerous states with statistically significant overcounts or undercounts.

States that did a better job of getting residents counted scored greater Electoral College and congressional representation, or did not lose seats in the House of Representatives. They also are now better positioned for the annual distribution of $1.5 trillion in federal funding in the coming decade.

Nothing can be done at this point to change how many congressional seats are allocated among the states, and neither can the data used for redrawing congressional districts be adjusted.

Undercounts signal people were missed, and overcounts suggest they were counted more than once or that people were counted who shouldn't have been.

Minnesota was one of eight states with an overcount, including New York, which lost out to Minnesota on the last congressional seat. New York's overcount amounted to more than 670,000 people. Rhode Island, also with a substantial overcount, may have kept a seat in Congress as a result too.

The 2020 census showed Minnesota's population grew by just over 402,000 people during the previous decade, reaching about 5.7 million. As a result of the overcount, the state's growth may not have been as robust as it appeared, Brower said.

Thursday's report showed that most of the overcount may have been caused by situations such as babies born after April 1, 2020, or people who died before that date being erroneously included in household counts, Brower said. The rate of people being counted in multiple places was very low.

Minnesota may have failed to count about 1.8% of its people, the report said. But this omission rate is much lower than the national average of nearly 6%.

Brower wasn't surprised by the news that Minnesota had an overcount, because the state has the nation's highest rate, at 75%, of people filling out the census forms without follow-up from census workers. In addition, various groups waged a strong campaign to engage residents to participate.

"There's more counting all around in Minnesota, typically," Brower said. "What we were really concerned about when we were doing engagement campaigns was missing people."

In Arkansas and Tennessee, an estimated 1 in 20 residents were not counted. Four other states — Mississippi, Illinois, Florida and Texas — also had significant undercounts.

In the remaining 36 states and the District of Columbia, the overcounts and undercounts were not statistically significant.

Arkansas, Florida, Tennessee and Texas did not direct as many resources as other states in encouraging residents to fill out census forms. Mississippi spent around $400,000. By contrast, Illinois allocated $29 million toward those efforts. The Minnesota Legislature allocated $2 million to the demographer's office. Historically, undercounted groups include racial and ethnic minorities, renters and young children.

Texas and Florida, two of the fastest-growing states over the last decade, had been expected to gain more congressional seats from the 2020 census than they did. Florida gained one seat and Texas gained two.

Thursday's report did not break down by demographic traits the effectiveness of the 2020 census at the state level, but a national report card released in March showed the Black population in the 2020 census had a net undercount of 3.3%, while it was almost 5% for Hispanics and 5.6% for American Indians and Native Alaskans living on reservations. Those identifying as some other race had a net undercount of 4.3%. The non-Hispanic white population had a net overcount of 1.6%, and Asians had a net overcount of 2.6%, according to the results.

The Census Bureau is not expected to release state-level results of racial undercounts, Brower said, despite the fact that she and others are asking for that information.

Academics and civil rights leaders are pressing the Census Bureau to revise yearly population estimates that traditionally have used census numbers as their foundation, and instead employ other data sources to produce a more accurate portrait of the undercounted racial and ethnic communities for numbers that help determine the distribution of federal funding. The Census Bureau has set up a team to explore this.

The Associated Press contributed to this report.