A lease has been signed at that location for Clinton’s campaign headquarters, according to a source familiar with the deal. The operation will occupy two full floors of the building, which is close to 12 subway lines and a dozen bus lines. The Clinton team will be taking the space as is – with no buildout.

Having the ink dry on the lease indicates that Clinton’s official announcement will be coming very soon. Federal Election Commission rules state that a candidate has only 15 days between conducting campaign activities and filing the official 2016 paperwork, and the lease signing could start the clock on an official launch.

A Clinton campaign spokesman did not respond to a request for comment.

On its website, the building at 1 Pierrepont Plaza markets it as “Modern Offices. Brooklyn Cool.”

Clinton’s chief of staff, Huma Abedin, checked out the building weeks ago and took a walking tour of the neighborhood. The Clinton team will be sharing part of the building with a branch of the brokerage Morgan Stanley, while across the street is the office of the U.S. attorney for the Eastern District of New York.

The new digs, however, couldn’t come soon enough for the roughly 35 staff members who have been based in New York — most of them volunteers with vagabond lifestyles.

During the day, they’ve clamored for whatever work space is available, especially because Clinton’s small personal office in Midtown Manhattan isn’t big enough for more than 20 people.

At night, most of the younger staff members are transients in the big city, staying on the couches of relatives, buddies and exes in Brooklyn and Manhattan, while preparations are being made for salaries, campaign-issued cellphones and apartments for the next 18 months.

“I’m sleeping on my brother’s couch and working out of Starbucks,” says one soon-to-be Clinton staffer who requested anonymity because he wasn’t authorized to speak on behalf of a campaign that doesn’t yet exist.

Longtime Democratic operative and Clinton loyalist James Carville said outsiders don’t understand the difficulties of building a campaign apparatus.

“The infrastructure is one of those things, between setting up press, field, and fundraising — it’s just enormous,” Carville said. “You don’t just flip a switch.”

The real estate is just one piece of the complicated process of building a campaign. Campaign manager-in-waiting Robby Mook has been making calls about top-level hires since January. He is now spending time in Iowa and New Hampshire, evaluating the scene on the ground.

Some of the newly hired staff in those states, as well as South Carolina and Nevada, are still unsure of their roles. Some quietly ask if they’ve been brought on so that Clinton can project strength with a huge campaign team, rather than to fulfill any specific operational objective in the coming days or weeks.

Clinton herself has been working from her home in Chappaqua, N.Y., and her small Manhattan office. But some senior Clinton aides are still preparing to move their families to New York — or, in the case of campaign chairman-to-be John Podesta — to shuttle between Washington and the campaign’s Brooklyn Heights headquarters.

There’s also some unease among Democrats who aspire to work on the campaign. After they weren’t included in an initial spurt of hires on the press team that came from quick conversations with incoming communications chief Jennifer Palmieri, some Capitol Hill and state party press secretaries are grumbling about being asked to fill out writing tests before being considered for jobs.

And some of those Democrats who have made it onto the 2016 team have hesitated at the small paychecks they’ve been promised once Clinton announces.

Still, some important pieces of the campaign operation are solidifying.

Former Obama pollster John Anzalone will lead the campaign’s polling of the first few states, while Patrick Burgwinkle — who worked for the Arkansas Democrats in 2014 — will serve as the press secretary in Iowa. The Iowa team has also spoken with former state Democratic Party executive director Troy Price and state operative Grant Woodard.

The Clinton team in South Carolina will be led by former aides to Rep. Jim Clyburn, except for the press team, which will likely come from Washington; the White House is bracing for a handful of mid-level departures for the Clinton camp in the coming weeks.

“One thing we’ve learned from the last two cycles is that it definitely takes time to build a modern campaign that incorporates all the things they’re talking about — organizing, data, and digital strategies, and that’s what’s happening now,” said one national Democratic strategist who is close to the emerging campaign team. “Part of it is planning, part of it is mental endurance, and part of it is just being able to come off the block as fast as you can.”

And part of it is just having time to pack. One Clinton Iowa staffer moved from Washington so quickly that the young Democrat’s parents are driving out to Des Moines to deliver the staffer’s belongings and car.

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