Copies of the 2010 Census forms are seen March 15, 2010. The 2020 U.S. Census will add a question about citizenship status, a move that brought swift condemnation from Democrats, who said it would intimidate immigrants and discourage them from participating. (Ross D. Franklin/AP)

The Senate has voted to confirm President Trump’s choice for director of the U.S. Census Bureau, filling a vacancy that lasted for a year and a half during the crucial run-up to the bureau’s 2020 decennial survey.

The new director, Steven Dillingham, was approved in a unanimous vote Wednesday night, six months after his nomination was announced. He will head a bureau that conducts the largest peacetime mobilization of the U.S. government, hiring hundreds of thousands of temporary staff to help count every person residing in the country while hewing to tight deadlines and budget considerations.

Census data is used to allocate $800 billion in federal funds, apportion representation in Congress, and redraw congressional districts.

Dillingham, 66, previously headed the Bureau of Justice Statistics and the Bureau of Transportation Statistics and served most recently as director of the Office of Strategic Information, Research, and Planning for the U.S. Peace Corps. He will fill the position for the remainder of a five-year term expiring Dec. 31, 2021.

Dillingham’s job will be particularly daunting given the controversies surrounding the 2020 count. The previous director, John Thompson, resigned in May 2017 amid controversy over the bureau’s funding. Since then, the bureau has been embroiled in legal battles over Commerce Secretary Wilbur Ross’s decision in March to add a citizenship question to the survey.

Seven lawsuits have challenged the addition of the question, and the matter could reach the Supreme Court. Opponents of the question say it is partisan and will depress response rates in immigrant communities; administration officials say it is necessary to enforce the Voting Rights Act. Critics of Trump say faith in the count also been shaken by revelations that some administration officials have said the confidentiality of the count, long a key component of it, could be up for “renewed debate.”

Insufficient funding has forced the bureau to cancel a significant portion of its testing of questions for the survey, and the company contracted to print the forms went bankrupt; the bureau has yet to announce a new one even as printing is set to take place this summer. The 2020 survey will also include a first-ever Internet response, sparking concerns about privacy and cyberattacks.

At an October hearing, Republican and Democratic senators grilled Dillingham on his views of the citizenship question. He declined to state an opinion, saying he would follow the ruling of the courts.

The Trump administration had earlier considered Thomas Brunell, a political science professor best known for his work on behalf of Republican redistricting plans and a book that argues against competitive electoral districts, raising fears of political influence over a bureau that traditionally steers clear of partisanship.

But Dillingham has not faced the same kind of criticism. Although some have raised questions about his lack of management experience with an agency as sprawling as the Census Bureau, former colleagues and lawmakers from both sides of the aisle described a man with a calm presence who understands the issues key to statistical data gathering.

“I personally was very pleased when I saw his name come up in the confirmation process,” said Katherine Wallman, who was chief statistician at the White House Office of Management and Budget and knew Dillingham when he led the Bureau of Transportation Statistics from 2007 to 2011. “I really think that he understands and knows about and most importantly respects the policies, process and principles that underlie the work of a fiscal agency in terms of its autonomy and its integrity.”

Especially at a time when the census faces so many challenges, she said, “It’s even more important that we have someone at the helm who understands the role of the agency and . . . how to uphold the work of a statistical agency even as they’re interacting with the political side.”

During Dillingham’s confirmation hearings, Sen. Brian Schatz (D-Hawaii), a critic of the citizenship question, told The Washington Post that he seemed “like a pro” and was “by all accounts a good choice and has the professional background and the credibility to make sure that we count everybody in America.”

In December, a raft of organizations including the NAACP, the American Sociological Association, the American Statistical Association, Nielsen and several Native American groups wrote a letter urging the Senate to confirm him and noting that Dillingham had pledged “to support a federal statistical agency culture of principles and practices grounded in relevance to policy issues, credibility among data users, trust among data providers, and independence from improper influences.”