The U.S. communities in danger of being overlooked in the 2020 census

About a quarter of the U.S. population —and more than 8 in 10 residents of Detroit — live in areas likely to be difficult for the census to accurately count next year, according to census data analyzed by the Associated Press.

Why it matters: "Hard to count" often translates to underrepresentation. The 2020 census will be the basis for allocating political power and government funding for the next decade.

• Unauthorized immigrant populations, large minority populations, non-traditional households, lots of young children, poverty and lack of internet access can all lead to undercounting.

The big picture: State legislatures will refer to the newest census data in redrawing congressional districts next year. The population counts will determine how many congressional seats each state will receive. The updated data will inform politicians of the demographics, economic status and family structures of the people they represent.

• As the nation rapidly moves toward a minority white society, one study this year found that next year's census could see the worst undercount of black and Latinx people in 30 years.
• Undercounting has long been an issue for racial and ethnic minorities, giving them and the issues their communities care about even less political weight.

By the numbers: In half of U.S. census tracts nationwide, more than 20% of the population is predicted to not respond to the initial census questionnaire.

• 86% of Detroit's population lives in hard-to-count areas — the highest of any city due to the tens of thousands of abandoned homes there, according to AP.

New Mexico (41%), California (40%), Texas (39%) and Nevada (37%) have the highest share of people living in areas with low census response rates.

• These states have some of the fastest changing racial and ethnic makeups, and many have been a focus for both Democratic and GOP political campaigns.
• The Trump campaign is trying to flip New Mexico in 2020.
• Democrats are becoming more competitive in Texas, long a reliably Republican state.

• Nevada has been a swing state and was only narrowly won by Hillary Clinton in 2016.

Between the lines: The 2020 census effort has been complicated by concerns about government underfunding, a failed effort by the Trump administration to add a question about citizenship to the questionnaire and technological concerns about answering questions digitally.

• In a statement to Axios, a spokesperson for the U.S. Census Bureau said they are spending $500 million on marketing and advertising — up from $376 million in 2010.
• "We've hired over 1,500 partnership specialists to work closely with local communities to ensure a complete and accurate count. Our partnership staff are hired locally from the communities we are encouraging to respond to the 2020 Census, especially the hard-to-count population."

States like California have allocated bigger budgets for efforts to engage with communities that have historically been undercounted.

• Texas, Louisiana and Florida are among the states that have invested nothing in ensuring an accurate census count.
• Despite hard-to-count concerns, Texas lawmakers have declined to pass bills to provide funding aimed at improving census response efforts. Nonprofits have stepped in, the Texas Tribune notes.