Alyssa Mastromonaco and Pete Rouse, right, to join HeadCount. | provided by Alyssa Mastromonaco Post-Obama: Working with The Dead

Their briefing books, filled with intricate details about President Barack Obama’s presidency, were adorned with the Grateful Dead logo.

Alyssa Mastromonaco, who managed nearly every aspect of Obama’s political rise, decorated her White House office with two framed photos of the psychedelic jam band.


Pete Rouse, Obama’s former chief of staff, still sneaks away to New York to catch a concert.

( Also on POLITICO: Obama goes rogue on Gitmo)

Now that they’ve left the White House, Rouse and Mastromonaco — two of Obama’s closest confidants — are becoming more deeply embedded in the rock ’n’ roll community. They both are gearing up to join the board of HeadCount, a voter registration group with close ties to the Grateful Dead and the rock ’n’ roll community.

Any number of corporations would shell out six-figure sums to have a close adviser to the president sit on their board. But Rouse, who recently joined a law firm as a policy adviser, and Mastromonaco, who is helping Obama set up his library, aren’t jumping at just any offer. In separate interviews, Rouse said he is being “very careful” about joining boards of directors, adding he has no plans to join other ones. Mastromonaco said she will focus on Headcount and her alma mater.

“You kind of get flooded with inquiries when you leave, so I’ve decided that these are my two for the foreseeable future,” she said in an interview. “Headcount and the University of Wisconsin.”

( Also on POLITICO: Dems give big to Senate Majority PAC)

HeadCount is a 10-year-old nonprofit group that deploys volunteers to concert venues across the country to register people to vote. The group is nonpartisan and seeks to register as many voters as it can, regardless of party. It says it has registered 300,000 people since 2004. Its focus extends across musical genres: This summer, volunteers will register voters on the Jay-Z and Beyoncé On the Run Tour.

There’s a healthy contingent of D.C. players on its board of directors: Republican strategist Gordon Hensley, Greenberg Traurig’s Diane Blagman and filmmaker Nicole Boxer, who is also the daughter of Sen. Barbara Boxer (D-Calif.).

Bob Weir, the former front man of the Grateful Dead, also sits on the board, and personally lobbied Mastromonaco and Rouse to join the organization. Over a dinner at The Hamilton — just a couple of blocks from the White House — Weir formally asked the pair to join the board.

“Alyssa and Pete have deep experience in mobilizing young voters,” Weir said in an email. “That’s our job here.”

( Also on POLITICO: GOP's Obamacare fears come true)

Mastromonaco and Rouse — who have both been with Obama since his days in the Senate — are notoriously private. But both agreed to interviews about their impending move — and their longtime love affair with live music.

Mastromonaco estimates that she’s been to more than 40 Phish shows. When she was in high school, a good report card allowed her to go to Albany, New York, to see the Grateful Dead. Every New Year’s Day for the past few decades, she’s listened to “Box of Rain,” a Grateful Dead staple.

When the living members of the Grateful Dead performed at the Verizon Center in 2009, Mastromonaco sat near the stage with David Axelrod, another Dead fan. Rouse has become friendly with Warren Haynes and Derek Trucks, members of the Allman Brothers Band. Mastromonaco said she “immediately” said yes to Weir’s offer.

( WATCH: What you don't know about Obama)

“The thing I love about [HeadCount] is it gives people the information to make their own decisions,” Mastromonaco said. “But it shows them how to be activists for the things that they care about. It doesn’t tell them what to do, it just tells them how to do it. I think that’s cool. When we get out there, and you have campaigns out there, and Democrats out there registering people to vote, I just think it kind of turns people off. Because they kind of assume that you only care about them voting [for your candidate]. This, to me, is just something that’s so wholesome because it’s nonstop, for 10 years, this is what they’ve been doing, and they want people to vote and show them how to vote.”

Rouse said, “I’m a Democrat, but what I appreciate about HeadCount is that it doesn’t care how you register, but rather just that you do register and participate. The summer concert season provides a great opportunity to deliver this message, and the idea that people are on site to register voters in real time appeals to me.”

“From a small ‘d’ perspective,” he added, “the goal is to get more people energized and involved. HeadCount has confidence in the power of ideas, and they are not here to tell young people how to vote, but just that it is important for their self-interest to vote.”