The decision to hand over the server, as well as a thumb drive of all her work-related emails to the Justice Department, represents an effort to blunt an expanding probe into her use of a private email account.
Clinton, now the Democratic presidential front-runner, "directed her team to give her email server that was used during her tenure as (secretary of state) to the Department of Justice, as well as a thumb drive containing copies of her emails already provided to the State Department," her spokesman, Nick Merrill, told CNN early Tuesday evening. "She pledged to cooperate with the government's security inquiry, and if there are more questions, we will continue to address them."
Merrill said in the meantime, Clinton's team "has worked with the State Department to ensure her emails are stored in a safe and secure manner."
The FBI, which is handling the matter, declined to comment Tuesday evening. David E. Kendall, Clinton's lawyer, did not immediately return messages seeking comment.
A senior Clinton campaign aide said the server hadn't yet changed hands as of Tuesday evening and Clinton's team is working with the Justice Department to arrange the logistics of the handover. The thumb drive, meanwhile, has been turned over. And Kendall, the aide said, has followed State Department guidance on safekeeping.
Clinton's campaign believes there are no emails from her State Department tenure on the server, since it was wiped clean after she turned over her work-related emails to the State Department, the aide said.
The aide said it's the Clinton campaign's understanding that the Justice Department isn't looking to reconstruct the server's history, but is instead concerned about the security of the emails today, since some are now classified, though they weren't classified or labeled as such at the time.
Boehner: 'It's about time'
For Clinton, the move -- which Republicans like House Speaker John Boehner have urged for months -- indicates her campaign sees a growing risk in the issue of her use of a private email server, which has stoked concerns about her trustworthiness.
"It's about time," Boehner said in a statement Tuesday night.
Since news broke in March of her use of a personal email address on a server kept in her Chappaqua, New York, home, Clinton has insisted that she's turned over all of her work-related emails to the State Department and deleted all others -- but wouldn't turn over her server to the government.
Clinton has been dogged by poll numbers showing that more Americans, by a margin of about 20 percentage points, say she's not trustworthy rather than trustworthy. A late July CNN/ORC poll found that 58% of all registered voters say it is extremely important that the next president be honest and trustworthy.
Rep. Trey Gowdy, who chairs the House Select Committee on Benghazi and has pushed for Clinton's emails for months, claimed credit for her decision to turn over the server.
"The revelation that Secretary Clinton exclusively used private email for official public business, and the multitude of issues that emanated from her decision, including this most recent one, demonstrates what can happen when Congress and those equally committed to exposing the truth, doggedly pursue facts and follow them," he said in a statement.
Senate Judiciary Committee Chairman Chuck Grassley, R-Iowa, said Clinton waited "a long time"