‘Good news for Massachusetts’: Population tops 7 million, as state keeps 9 congressional seats after 2020 Census

New England will for now maintain its 21-seat clout in the US House of Representatives, where for the first time in a half-century none of its six states lost a seat in the country’s decennial census, according to data released Monday by federal officials.

Massachusetts’ population grew to slightly more than 7 million people last year, enjoying the largest increase of any New England state over the last 10 years at 7.4 percent, helping to retain its nine congressional seats. Rhode Island, now with nearly 1.1 million people within its tightly drawn borders, defied expectations by keeping the two House seats it has held since 1930.

The region’s ability to hold onto its seats stood in contrast to a shifting landscape elsewhere, as New York, Pennsylvania, and California were among seven states to lose a seat — with New York coming just 89 people short of maintaining its size in the House, according to a census official. The lost seats continued the steady, decades-long erosion of the Northeast’s influence on Capitol Hill, as more of the House’s 435 seats flowed south and west.

Texas added two seats, bumping its total to 38, to lead a group of six states that saw their delegations expand while population growth nationwide slowed to its second-lowest rate in the country’s history.

How Republican-led Legislatures in some of those states redraw their boundaries could help eventually reshape the House by potentially making it easier for Republicans to capture districts and ultimately win back control of the chamber, costing Massachusetts’ all-Democratic delegation its own positions of power. Representative Richard Neal, for example, currently chairs the powerful Ways and Means Committee, and Representative Katherine Clark is the chamber’s assistant speaker.

Even still, the 7,029,917 people counted as Massachusetts residents exceeded estimates for the state by more than 100,000 people, and the state’s rate of growth far exceeded the 3.1 percent it grew in the decade before 2010, when Massachusetts lost a congressional seat.

In fact, Massachusetts had lost a seat following three of the previous four census counts, whittling down what was a 12-seat delegation after 1970. It was that census 50 years when New England last avoided losing a seat.

“We were relieved. . . . Today is good news for Massachusetts,” Secretary of State William F. Galvin said of Monday’s figures, though he warned of potential challenges in redrawing the state’s political boundaries to account for expected higher growth in the eastern part of the state.

For example, his office estimates that the Eighth District, which encompasses South Boston and parts of the South Shore, now has 822,778 people living in it — far above the 781,102 each district is expected to have after they are redrawn later this year. Meanwhile, the First District in Western Massachusetts is estimated to have 736,589 as currently drawn.

Overall, the United States population grew by 7.4 percent since 2010 to hit 331.4 million people, according to initial data released by the US Census Bureau. Utah saw the highest population growth, increasing by 18.4 percent, the Census Bureau said. West Virginia lost 3.2 percent of its population.

Districts for the 435 seats in the US House of Representatives are redrawn each decade based on the census, with fast-growing states sometimes gaining seats at the expense of slower-growing ones. The census also is used for redrawing state and local political districts, determining the distribution of $1.5 trillion in federal spending each year, and reordering how many Electoral College votes each state gets.

Massachusetts officials largely expected the state to retain hold of its nine seats despite a tumultuous counting process. The census was buffeted by COVID-19-related delays, legal wrangling, and then-President Trump’s attempt to block undocumented immigrants from being included in the count.

In Rhode Island, which was widely viewed as in danger of being slimmed to just one House seat, the news was also met with relief after the census counted 1,097,379 people in the state, an increase of 4.3 percent from the 2010 Census.

The surprising news avoids a potential showdown between Representative David N. Cicilline, an increasingly high-profile Democrat who served as an impeachment manager for former Trump’s second impeachment trial, and Representative James R. Langevin, a Democrat who has built up 20 years of seniority after becoming the first quadriplegic to serve in Congress.

“The big winners are the people of Rhode Island in terms of maintaining political clout,” Langevin said in an interview. “Having two voices and two votes is much better than having one.”

Vermont remained the region’s least populated state, with 643,077 people, an increase of 2.8 percent. Connecticut, now with 3,605,944 residents, saw the smallest population growth in New England at less than 1 percent.

Monday’s release was only the initial batch of data and did not include more detailed information, such as population counts for specific cities that will help state lawmakers redraw congressional and state legislative districts. It also didn’t include a breakdown of populations by race, age, or other demographics.

The UMass Donahue Institute, which runs the state data center, had estimated that Massachusetts’ 2020 population was 6.89 million people, an increase of 5.3 percent from the 6,547,629 residents counted in 2010, according to Galvin’s office.

Given the unprecedented challenges with the count, federal officials said the more detailed data that state officials need may not be released until the end of September, six months later than usual.

Galvin and local officials have also openly fretted that the Supreme Court’s decision last year allowing the Trump administration to halt the census count early in October could lead to undercounting in already difficult-to-count communities such as Lawrence and Chelsea, which have high populations of renters and immigrants.

When census takers ultimately started going door to door last summer, officials feared their effort was too little too late. College students, for example, who are typically counted as residents of the community where they study, were gone. Other residents had moved temporarily because of the pandemic.

Galvin has also repeatedly said he believes that Trump used the census as a political tool to punish Democratic states such as Massachusetts, which went overwhelmingly for Biden in the 2020 election. The seven-term Democrat said he had planned to sue federal officials if the state’s population count fell far enough to cost Massachusetts another congressional seat.

That situation didn’t come to pass. Beth Huang — executive director of the Massachusetts Voter Table, which helped lead local efforts to ensure all citizens were counted — said the initial figures show the state’s growing immigrant population is likely helping drive the population increase.

The better-than-expected figures also indicate that census officials were able to use official documentation to count groups such as college students who were otherwise pushed off campuses, and out of reach of census-takers, at the start of the pandemic.

“It looks like the universities and the census accurately counted those,” said state Representative Michael J. Moran, a Brighton Democrat who helped redraw the state’s political lines after 2010 and is again helping lead the Legislature’s efforts this year.

By Matt Stout

Edward Fitzpatrick of the Globe staff contributed to this report.