Sen. Barbara Mikulski (D-Md.) described Hayden, 63, as a transformational leader who is the perfect candidate for the job of modernizing the library, an agency with a $620 million budget and 3,200 employees.
"She's proven herself to be a skilled manager of large complex projects. She moved the Enoch Pratt into the digital age," Mikulski said. "Our nation will be well served by her confirmation."
The vote came five weeks after the Senate Rules Committee unanimously voted to recommend Hayden to the full Senate. But the nomination stalled after conservative lawmakers raised concerns about positions she held 13 years ago, when she was president of the American Library Association.
Hayden earned a doctorate from the University of Chicago. Before her tenure in Baltimore, she was chief librarian of the Chicago Public Library. She has served on the National Museum and Library Sciences Board since 2010.
Hayden was widely praised for keeping Baltimore's libraries open during last year's protests over the death of Freddie Gray while in police custody. As head of Enoch Pratt – which has 22 locations, 500 employees and a $40 million annual budget – Hayden oversaw the opening of the first new branch in 35 years and the ongoing $112 million renovation of the central branch. She has upgraded its technology and added such programs as college and career counseling.
Hayden, who was appointed by President Obama in February, thanked the staff and board of the Enoch Pratt for their support and said she looks forward to working with her new staff. "I will be honored to build on the legacy and accomplishments of my predecessors in this position, to be part of a continuing movement to open the treasure chest that is the Library of Congress even further, and to make it a place that can be found and used by everyone," she said in a statement.
Founded in 1800, the Library of Congress serves many functions. It is the research arm of Congress, provides legal advice to its members, public programs and assistance to scholars, and operates the Copyright Office.
It faces many challenges. Last year, a federal watchdog agency issued a critical report on the library's technological shortcomings, echoing the findings of similar investigations going back 20 years. The report found mismanagement that cost taxpayers millions of dollars and outdated systems that threaten the ability of the Copyright Office to function. Six months later, the Copyright Office's online registration system was down for a week.
As president of the ALA, Hayden opposed parts of the Patriot Act, which librarians believed invaded the privacy of library uses. During her April confirmation hearing, she was challenged on this, as well as the ALA's opposition to a law requiring libraries to install Internet filters to block pornography.
At her confirmation hearing in April, Hayden explained her position on the filters, saying that the technology at the time was inadequate and hampered access to important health information. A search for "breast cancer" would be blocked, she said.
"Since that time, technology has improved," she told the committee. "My library, the Pratt Library, in its state role, has installed filters."
Sen. Roy Blunt (R-Mo.), chairman of the Rules Committee, addressed this before Wednesday's vote, saying he asked Hayden specifically about her position on the Child Internet Protection Act. "At the time, according to Dr. Hayden, the filters were not as sophisticated as they are today and they had a tendency to over-filter," he said. "However, she made it clear that her view on pornography was it has no place in public libraries."