Washington CNN  — 

As Hillary Clinton’s expected April presidential launch nears, her already sizable campaign apparatus is moving into place and getting close to signing a lease for office space in Brooklyn.

Clinton and her team have recently coalesced around the New York borough, according to multiple sources, and are nearing a deal for office space at the MetroTech complex in Brooklyn.

A lease has not been signed yet, according to a source with knowledge, but very serious negotiations are ongoing and the Clinton team settled on Brooklyn after eying other locations around New York City. She ran her 2008 presidential campaign from Virginia, just across the Potomac River from Washington.

The Clinton team is still preparing for an April announcement, several top Democratic aides, donors and supporters say, although the precise date still remains up for discussion. Dozens of campaign staffers, who have been sworn to secrecy after being notified that they were being hired, have been told to report to New York by late March.

Clinton has been conducting personal interviews with several potential advisers at her home in Chappaqua, while her top aides have been assembling a communications, fundraising, political and social media team.

Clinton supporters see a number of benefits in Brooklyn, including ease of attracting talent to the New York area and the fact that it’s known for ethnic and socio-economic diversity.

On the downside, some Clinton supporters have expressed concern with being closely associated with New York City, and in particular Wall Street, which is only two subway stops away.

The campaign headquarters also creates a logistical challenge for staffers in a city of high rents. The campaign is asking supporters in New York if anyone who can open their doors and take in young workers.

The email controversy that has engulfed the Clinton operation for nearly two weeks did not accelerate the timing of her presidential announcement, several top Democrats said, but it did underscore the need for a full-scale campaign apparatus to deal with the incoming criticism.

“I think folks are realizing now more than ever that they need to announce earlier rather than later,” a source with knowledge told CNN. “The whole argument that she is left undefended without an official apparatus around her just became magnified 100 times over with this email issue.”

The scale and scope of the campaign will ultimately reach into the hundreds, but aides said it would grow gradually.

A larger grassroots operation is planned for Iowa, site of the first-in-the-nation caucuses, where campaign workers will train over the next several months before being dispatched to battleground states. New Hampshire, home of the first Democratic primary, will also be used as a training ground for field and political staffers.

While Clinton isn’t expecting an aggressive Democratic primary contest, advisers said they realized they have little time to waste and are approaching the race as though they already have a dozen challengers – namely the prospective Republican candidates who are trying to distinguish themselves by forcefully criticizing Clinton.

Because of that undisputed frontrunner status, though, Clinton and her team have had their pick of top talent around the country without having to fight with other campaigns.

In New Hampshire, the nascent presidential campaign plans to hire three advisers to Sen. Jeanne Shaheen’s re-election bid in 2014 to lead Clinton’s New Hampshire operation, according to Granite State Democrats.

Mike Vlacich, a longtime New Hampshire operative, will be Clinton’s state director, Kari Thurman, the Shaheen campaign’s political director, will fill the same role for Clinton, and Harrell Kirstein, the Shaheen campaign’s communications director, will run Clinton’s communications shop.

The all-but-announced campaign has also tapped Iowa leadership.

Matt Paul, a longtime adviser to former Iowa Gov. Tom Vilsack, will lead the Clinton’s Hawkeye operation. Paul, who serves as a top adviser to Vilsack at the Department of Agriculture, is returning to Iowa for the job and is expected to be in place by the end of the month, according to Democrats in the state.

Joining Paul in Iowa will be Brenda Cole, a longtime Iowa operative, and Lily Adams, currently the deputy communications director at the Democratic National Committee, according to Democrats in the state. Adams will runs Clinton’s communications shop in the Hawkeye State and Cole will be her political director.

As CNN reported on Thursday, Clinton has started to line up a press operation, too, an effort that became a priority when was seemingly left undefended during a recent controversy over her exclusive use of a private email system while she served as secretary of state.