'You have to make it fun': Jill Biden opens up about life on the campaign trail

She's now logging grueling hours advocating for Joe Biden's 2020 bid.

The pace of the campaign often keeps Joe and Jill Biden, a married couple of 42 years, apart. Jill Biden spoke with CNN in Concord, New Hampshire, where she shared how she stays handles the pressures of the trail.

"He came home the other night, I hadn't seen him, probably for a week. And so I think it's important in a marriage that you keep that spark going," she told CNN in an interview in Concord, New Hampshire. "Before I saw him, I lit the candles. I put on the fire. We sat down and we started talking. And like always, it's always about the kids and what's this person doing or that person doing, or the grandkids. But after 20 minutes, we were like, 'God, we're exhausted.' So we went to bed."

"I'm telling you we have very few moments together, so I tried to make the most of those moments, and I don't talk politics," she said.

While on the road, she stays in touch with her children and grandchildren over Facetime, text and phone calls. Her 21-year-old granddaughter Finnegan is campaigning on her own in Iowa this weekend, and her 15-year-old granddaughter Natalie will soon introduce her at campaign events later this month.

Biden, an avid runner, tries to keep up her exercise regimen on the campaign trail with barre classes and cycling, an activity she enjoys doing with her grandchildren and hopes they will cherish as a memory. For Christmas one year, she bought her husband a Peloton bike, which has been cited as part of his workout routine.

Drawing on her roots as an English professor, Biden loves to read. She recently finished "Just Mercy: A Story of Justice and Redemption" by Bryan Stevenson and hopes to soon start "Red at the Bone" by Jacqueline Woodson. She ends most of her days on the road with her staff, eating a healthy meal and enjoying an occasional glass of wine. ("Red," she said enthusiastically when asked her wine of choice.)

Biden says she's developed relationships with the spouses of some of her husband's current and former rivals. She described Doug Emhoff, the husband of Kamala Harris, as "a lot of fun, always positive," says she's known Bernie Sanders' wife Jane for "years and years and years," and noted Amy O'Rourke, Beto O'Rourke's wife, is "really a very kind, nice person."

She told CNN it can be hard for spouses to watch as the Democrats pounce on each other at debates.

"At the debates, what they do is they sit the families together. So, there you are sitting there, and then you see somebody attacking, you know, well for me, for my husband if they're attacking him. And you can't say, 'What, are you kidding me?' she said. "You have to just sit there, because their spouse could be sitting right next to you. But I think the good thing is, we know what our roles are and that we're sort of all in this together. And I really, we're friendly, we're definitely friendly towards one another."

Despite the chaotic nature of the campaign, Biden says she draws energy from life on the trail.

"It's invigorating," she said. "Look at those women I just met! I mean, they were so much fun to sit down and talk with them about what they were reading and what they were doing and we were talking about the environment."

"I meet really interesting people all over the country and hear their stories," she said. "You have to make it fun."