Early in the morning I board Hillary's Ohio-bound plane in New York City. She'd invited me to come along for the ride as a friend, not a colleague; I'd joined her on previous trips, and we had visited diners and knocked on doors. It's Halloween, so the campaign team passes around cowboy hats and goofy masks for everyone to wear, and we share a laugh as we all put them on.

The plane is stocked with hot sauce. Hillary loves protein breakfasts—scrambled eggs with garbanzo beans—spiced up with lots of hot sauce. Everyone on the plane uses it. You feel like a wimp if you don't. Hillary has always appreciated spicy food—when she was First Lady, she grew little pots of hot peppers that were wicked, wicked hot.

MORNING

Our first stop is Cleveland, to a surprise visit at a diner called Angie's Soul Cafe, where we meet Rep. Marcia Fudge. Everyone's shocked when we walk in: "It's her! It's her!" They all run over and take photos. One woman puts her arm around Hillary and says, "I'm with you, Hillary." Hillary turns, looks at her and says, "No, I'm with you."

With Rep. Marsha Fudge at Angie's Soul Cafe.

With Rep. Marsha Fudge at Angie's Soul Cafe.

AFTERNOON

In the car along the way to a rally at Kent State University, Hillary and I catch up on our families and mutual friends. She wants to know: "Where's so-and-so? How are they doing? Oh, I heard so-and-so had a baby. Have you seen the baby? Oh, I just heard they got married. Do you have any photos?" She asks about my son, who's getting ready to travel to China with a school program, and about my husband, a cardiologist. We laugh about the time she'd asked him to teach her some of his exercises. He's very fit, and showed her the P90X regime, which is really, really hard. She did it for like 15 minutes, then looked at him and said, "Rob, this one's just not for me." She's into yoga.

EVENING

We fly to Cincinnati for a riverfront event with former Rep. Gabby Giffords. They talk privately after the rally; it's clear they're friends. Then it's back to the plane. Hillary loves to hang with her staff—a pretty small traveling team of around six people. She'll often ask her traveling Press Secretary, Nick Merrill, "What's going on? Whatcha hearing? What are you doing?" We finally land back in New York around 3:00 A.M. Originally I was going to be with her for just today, but she asks, "Why don't you stay for the week?" Okay!

In Cincinnati with former Rep. Gabby Giffords and Giffords' husband Mark Kelly

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We get a super-early start in Florida—I flew in late last night after packing for the week. I've brought Hillary some presents to celebrate her recent birthday: first, a Division champion hat for the Chicago Cubs, since she's a huge fan. I'm from Cleveland, so I'm an Indians girl; I also brought along a Cleveland Indians scrunchie as a joke. When she was Secretary of State, she had long hair and really believed in scrunchies. We were always telling her, "You cannot wear those." She would say, "Why? They're really comfortable." President Clinton's Chief of Staff, Tina Flournoy, once gave Hillary the rapper name of "Li'l Scrunchie." When I hand Hillary the Indians scrunchie, she says, "Well, I can't wear that one."

Meeting voters in Florida at an early voting location.

Meeting voters in Florida at an early voting location.

MORNING

We head to a strip mall in Fort Lauderdale for a surprise visit. Suddenly, people are racing down the street. She gets her energy from these events—known as off-the-record, or OTR, visits—because it's where she hears personal stories from people. They come up and say things like, "My son is addicted to heroin…you're going to find a solution, I know." She writes these stories down on little cards and puts them in her pocket to review and discuss later with her team.

LATE MORNING

In Las Vegas we surprise casino employees: "I love these behind the house visits," Hillary says before we head in. Why? I ask. "You'll see!" she says. "They're awesome!" And the instant she walks in, there's a burst of energy—people cheering, literally jumping over tables and standing on chairs to meet her and take pictures. The agents try to clear a path for her as she moves through the crowd.

Greeting employees at the Mirage casino in Las Vegas .

AFTERNOON

That afternoon we head to Tempe for an event at Arizona State University. There's a sea of 15,000 students, along with Rafael Lopez from Tucson, the father of fallen soldier Damian Lopez Rodriguez, who introduces Hillary. She's backstage and can't hear what he's saying above the noise, so she keeps asking staffers to quiet down. After her speech, she shakes hands with everyone in the rope line. She finally finishes late at night, and her former State Department senior advisor, Philippe Reines, finds a broadcast of the Cubs game—the final game of the World Series—on his iPad. "We're going to watch the last moments right here," he says. When the Cubs win, she and campaign aide Connolly Keigher throw their arms up in celebration, right there on campus. A classic moment.

Cheering on the Cubs

Around 4:00 A.M, we're back on the plane, this time to Raleigh, North Carolina, where we drive to Durham and North Carolina Central University.

In the car, Hillary's doing constant radio shows, and also keeping in touch with her family. She talks with Chelsea and her husband, Marc Mezvinsky. President Clinton usually checks in two or three times a day, and I'll overhear her talking to him: "How are things going? How are you feeling? I'm good. Where are you? Oh, you're there. Oh, great. Did you see so-and-so? Super, did you hear they just had a grandchild?"

By far, her favorite road trip activity is FaceTiming with her granddaughter, Charlotte; she often comments on what a great mother Chelsea is. Hillary's face lights up when they connect: "Hello, Charlotte, it's Grandma!" Hillary carries a picture of Charlotte in a locket on her charm bracelet, and she jangles it for her granddaughter to see.

Hillary poses for a selfie with Pharrell Williams backstage before a rally.

AFTERNOON

At North Carolina Central, a historically black college, we're supposed to pay a surprise visit to some students at an outside campaign table. Pharrell Williams joins us. Students see her and start texting friends to hurry over; the crowd grows very quickly. All you can hear is "Hillary!" Next we head to a rally with Sen. Bernie Sanders. Hillary's high-fiving little girls sitting on their dads' shoulders, and doing selfies with young women. She's a selfie expert now; she'll say, "Oh, I can do that. Give me your camera."

Later that night we fly back to New York, touching down once again in the early hours. Everything's back-to-back-to-back; you get so tired that you start to lose track of the time zones and fall asleep in your clothes. Hillary doesn't seem tired at all.

AFTERNOON

We head to Pittsburgh. During an event at the Steelers' Heinz Field, we meet up with Dan Rooney, former U.S. Ambassador to Ireland, and entrepreneur Mark Cuban, among other supporters. Hillary's thrilled to be at the stadium: football was a big deal in her family; her father and brothers all played. Former Steelers stars Franco Harris and Mel Blount are there: "Wow! Legends!" she says when she sees them.

Capricia and Hillary walk through the Steelers

EVENING

Next up is a rally in Detroit, where Rev. Wendell Anthony introduces Hillary with warmth and zeal. Then it's back to Cleveland, for a concert that evening with Beyonce and Jay Z. When Hillary hits the stage, the stadium explodes. People pound the seats, screaming "Hillary! Hillary!" It looks like she has to pause for a moment to digest it. Beyonce and Jay Z swoop in and lead her to the center of the stage by the hand, like, We've got you! Watching them perform, Hillary tells me, "Look at that talent. It's just amazing." For one number, the backup dancers wear Hillary-inspired blue pantsuits.

Backstage with Jay Z and Beyonce.

Back on the plane, Hillary has a surprise for us. She'd been given a bottle of tequila by the hosts of the popular Univision show El Gordo y la Flaca. It's time to bust it out, she says to Director of Communications Jen Palmieri: "I think we should all have a little tequila!" We don't have proper glasses, so we drink it out of coffee mugs instead.

Hillary with Sybrina Fulton in Miami.

Hillary with Sybrina Fulton in Miami.

MORNING

After arriving in Miami at around 3:00 A.M., we head to Little Havana for surprise visits. Our first stop begins with a poignant moment: a meeting with Sybrina Fulton, Trayvon Martin's mother. Hillary has met her many times and admires her tremendously. "How can I help?" Hillary asks, hugging her. As a mother herself, Hillary feels such a kinship with the Mothers of the Movement, a group of women who have lost children to gun violence or in encounters with police. The two women talk about overcoming the death of a child and the problem of young black men being shot and killed in America.

AFTERNOON

Next up, a rally in Little Havana. As Hillary speaks, the sky opens up. Rain pours down like crazy. Hillary's soaked; she howls with laughter and high-fives other drenched people.

Hillary in the rain.

EVENING

We're heading north again, this time to Philadelphia. We start off at a coffee shop, where we meet some contest winners—two young women and their moms—who'll join Hillary at a Katy Perry concert that night. Hillary is immensely curious about their lives. After the concert—another heart-pumping event—we meet up with old friends at the Logan Hotel, people who worked for Hillary in the White House, in the Senate, at the State Department, along with pals from Wellesley and Yale. All her buddies are here, and they're pulling out their phones, showing her baby pictures and wedding pictures, asking for her advice. She's been a mentor to so many, and it's pretty spectacular how she remembers details about everyone she knows. When I finally go to bed, I'm so tired and hungry from missing dinner that I wearily grab some chocolate-covered almonds from my bag—that's all I can muster to eat.

The next morning I wake up and think, Why do I feel gooey? I look in the mirror: there's chocolate smeared all over my hair and face. Apparently I was so wiped out last night that I fell asleep while eating those almonds. Hillary laughs when I tell her about it. The road is not for lightweights.

MORNING

We start the day with a Sunday service at Mt. Airy Church of God in Christ in Philadelphia. Gospel singer Bebe Winans sings beautiful hymns; New Jersey Sen. Cory Booker joins her on stage. Hillary loves these services. She does not wear her faith on her sleeve, but she's an incredibly spiritual person.

Attending Sunday services at Mt. Airy Church of God and Christ.

As we leave the church, Minyon Moore, a brilliant strategist helping with the campaign, whispers something in Hillary's ear. I don't know what she said, but they are both tearing up. We hear the church choir break out in song. Everyone's feeling the emotion of this historic time. So many of us are supporting Hillary because we've admired her work for so long, and we're always thinking about what this election could mean for young women, and for women around the world. Are we finally going to break that glass ceiling?

Looking on as LeBron James speaks during a rally in Cleveland.

EVENING

After flying to Cleveland to see LeBron James, who's endorsing Hillary, we head to Manchester, New Hampshire. Hillary's dear friend Sen. Jeanne Shaheen is there, and they hug immediately. Gold Star father Khizr Khan gives a moving talk about the Constitution and what it means for his family. People are hugging Hillary, recognizing what a long battle it's been. Once again, we arrive back in New York in the wee hours.

Speaking to Gold Star father Khizr Khan in Manchester.

It's the day before Election Day. Hillary's wearing her signature red suit, the one she wore in the second debate. When her car drives up to the plane, she's FaceTiming with Charlotte: she gets out and shows Charlotte the plane, the reporters, the whole scene.

MORNING

It's a gorgeous day for an outdoor rally in Pittsburgh. It's so packed that the people who couldn't get in are cheering from across the street. After giving her talk, Hillary runs up to say hello to the crowd, especially the many little girls. During a campaign, you never feel that a win is inevitable—you're always on pins and needles—but we are definitely feeling the growing momentum...the overwhelming hope and support for Hillary.

On the last day of campaigning, Hillary meets voters in Pittsburgh.

LATE AFTERNOON

In Detroit I see another army of young girls waiting to meet Hillary at a rally here—hoping to get a handshake, maybe a selfie. Later we met up with Rep. Debbie Dingell, another longtime friend, in a packed bar. Huge guys—locals who hang at the bar after work—come up and hug Hillary. One towering man envelops her, dwarfing her, then introduces her to the entire bar, person by person.

At a bar in Detroit.

EVENING

We head back to Philadelphia for a giant concert—I think around 35,000 people show up. President Clinton and Chelsea are there; then President Obama and the First Lady arrive. Everyone's giving each other enormous hugs. President Obama is one of the greatest huggers, I swear.

President Barack Obama with Hillary during a rally in Philadelphia.

Bruce Springsteen comes out and riles up the crowd. Chelsea's next, then President Clinton, then Michelle, and finally President Obama, who introduces Hillary. The momentum's building, and we're all feeling really good. But we aren't done yet.

LATE NIGHT

Capricia, Hillary and Jon Bon Jovi.

We're in Raleigh again for a 1:00 A.M. rally with Lady Gaga. Jon Bon Jovi is with us—he'd played in Philly and spontaneously said, "Let me come. I'll play in Raleigh, too." He and Lady Gaga sing "Livin' on a Prayer" together, even though they've never rehearsed it. Looking around, I see women with signs mentioning Hillary's mother, Dorothy. I think, Yeah. This is about Dorothy and Hugh—Hillary's father—and all of the hard-working middle class people like them who have fought for the dreams of their children.

When we fly back to New York, a huge crowd of supporters surrounds the plane, cheering and clapping. It's around 4:00 A.M. Hillary heads to her home in Westchester County; the rest of us arrive in the city at dawn.

The big day is here. I slept for about an hour last night…if that. Just too excited. I'm with the campaign team at Manhattan's Peninsula Hotel. Hillary's due to come in from her home in Westchester. I run out and buy an outfit that afternoon, preparing for a hopeful celebration that night at the Javits Center, a convention center with a glass ceiling.

Hillary and former President Bill Clinton vote on election day morning at Douglas Grafflin Elementary School in Chappaqua, New York.

My plan is to ride with Hillary in her motorcade to the party. Early in the evening, I'm sitting in my room in my robe, velcro rollers in my hair, watching TV as the results begin to roll in. A couple of friends drop by. The early results are pretty much what we expected and we don't think much of it. So I start getting ready for the event, putting on my outfit, filled with anticipation.

Campaign members are spread out in rooms across the hotel; there's massive security everywhere. I make my way to one of the rooms where people are gathered, to watch more results before we head to the Javits Center.

Awaiting the results at Hillary's election night event at the Javits Center.

Gradually, it begins to become clear that things are not going our way. But still, I don't really acknowledge it. I keep thinking, Wait a minute, there are so many numbers still outstanding. Time becomes a blur. The numbers keep coming. Somehow it is around 11 P.M., and it starts to dawn on me that this woman—who I believed would have made an extraordinary leader for our country—is not going to be president after all.

People ask if I want to go to the Javits Center, but I simply do not have the heart. I sit around the hotel with the campaign team and eat big bowls of ice cream, late into the night. Hillary is there, but I'll let her reveal how she felt about that night.

When Hillary makes the call to concede the election, around 2:30 in the morning, I finally accept what's happened. It's my snap-to-reality moment. I think of all those years she put in, and how people will never get a chance to see how truly great she would have been as president. The loss of that possibility is my greatest heartache. She didn't have to take on this grueling campaign. She didn't have to put herself through any of this. She did it because her life has always been about serving others. Hillary cares so much about this country, because she cares about people —and I know that once we've all had time to let this sink in, we'll need to keep that spirit alive by listening to each other as Americans.

I think about the week I'd just experienced: how we'd get on the plane after a long day and I would collapse in a chair, while she'd pick up piles of papers and start reading—briefings, newspapers, magazines, handwritten notes to herself about people she had met. And she'd been doing this for 19 months. I got to see her work hard, and have a blast doing it. She gave a million percent of herself. It's an honor to have witnessed it.

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