Elizabeth Warren was hiking on the Pacific Crest Trail in central Washington with her husband last fall and texting nature photos back and forth with Jay Inslee, the state's governor, who at that moment happened to be hiking in the San Juan Islands with his wife.

Inslee had recently dropped out of the 2020 presidential race, while Warren was fresh off a sizable rally under Seattle's Space Needle, making them a part of a very small club of people on planet Earth who know what it's like to be put through the peculiar wringer of trying to become leader of the free world. So they got lunch and talked about climate policy.

"It's a very personal experience to run. Running for president can be thrilling but also very lonely," Warren told NBC News in a recent interview.

"The candidate stands alone," she added, opening up about the experience of running. "Everyone else, they have good advice, you know, plenty of people around. But it's the candidate who's got to go out onstage. It's the candidate who has to make the final decision and stand by the fallout. And that makes it really tough."

Warren, a consummate call-everyone-she's-ever-known-on-their-birthday type, is hoping to get through the rigors of a presidential campaign and back atop the field with a little help from her former rivals-turned-friends.

"With everyone who's dropped out that I've spoken with — which I think is close to 100 percent of them — it's been in part to thank them for running and to say, as only another candidate can, I know it's hard," she added.

On the campaign trail, Warren goes out of her way to mention incorporating the signature policy issues of "Cory" (Booker) or "Julián" (Castro). It's a nod to the people she sees less often these days, but it's also a tactic to bolster her pitch that she can build coalitions from the constituencies of the candidates who've dropped out while also drawing a subtle contrast with front-runner Bernie Sanders' more strident brand of progressivism.

Sanders says he has little tolerance for what he sees as frivolous pleasantries. "If you have your birthday, I'm not going to call you up to congratulate you," he told The New York Times editorial board.

And while it's common for candidates to reach out to opponents who drop out and offer gracious platitudes, Warren's conversations with some former candidates have gone deeper.

Let our news meet your inbox. The news and stories that matters, delivered weekday mornings. This site is protected by recaptcha

Former Rep. John Delaney of Maryland sparred frequently with Warren over health care before he dropped out days before the Iowa caucuses. One debate back-and-forth between the two even got so tense that Delaney's "cause of death" on Wikipedia was changed to "Senator Elizabeth Warren." Still, when he dropped out, his phone was ringing — from everyone, but memorably from Warren.

"Everyone was very nice. It was just that the call with her was quite lengthy and quite in-depth," he said. "That demonstrated to me that she has a trait that you don't always find in politicians, which is that she's not entirely self-absorbed. She actually listens."

An aide to another Democratic politician called the approach "micro-touches," using the parlance of the sales world, which has long been part of Warren's modus operandi.

Download the NBC News app for breaking news and politics

Running for president is weird. You're everywhere and nowhere all at once, smashing through time zones and news cycles with little sleep and less privacy. Almost every interaction with another human comes freighted with the possibility and peril of becoming a viral moment.

"I feel like I'm living in a movie that is running at high speed with everything coming by so quickly," Warren said.

The people who understand this best, of course, are the other candidates. But there's not much time nor trust on the campaign trail to sit down and commiserate over a beer with someone you're trying to defeat.

Sens. Kamala Harris of California and Kirsten Gillibrand of New York are part of the even smaller club-within-a-club who know what it's like to run as a woman.

"Kamala and Kirsten, in particular, ask me am I getting rest? Am I eating? And am I having some fun out there?" Warren said.

But she's also gotten mathy with Andrew Yang, with whom she says he has a running joke about using some of the same data sources in their writing (she said she was impressed with his book).

It's part of a rhetorical effort to pitch herself as the only candidate who can bring together all of the Democratic Party. It was once seen as a "unity pitch," but Warren's allies and aides now talk about it as a push for coalition building, one bolstered by Warren's frequent warnings about returning to the "factionalism of 2016."

Warren has back-burnered the unity pitch after disappointing finishes in Iowa and New Hampshire in favor of hammering Mike Bloomberg at the last debate, which earned rave reviews and an influx of campaign cash but didn't lead to a win in Nevada. She'll have another shot at Bloomberg in Tuesday's debate in Charleston, South Carolina, but she was never expected to do particularly well in Saturday's South Carolina primary, although she can hope for better on Super Tuesday, March 3.

Warren in particular singled out Castro, who endorsed her and has become her chief surrogate since he ended his own campaign. They've known each other since the Obama era, when they'd have lunch and she would skip the small talk to push Castro, who was running the Department of Housing and Urban Development, on what she thought he could be doing differently. "Push harder, harder, harder," she told him.

Warren will need a lot more help to regain a clear path to the nomination and, despite the outreach, has received the endorsement of only one former candidate, Castro, while Sanders has those of two (New York Mayor Bill de Blasio and Marianne Williamson), as does former Vice President Joe Biden (Reps. Tim Ryan of Ohio and Seth Moulton of Massachusetts).

But she takes joy in little moments, like when people on her staff noticed that a recently hired former aide to Harris still had a "Kamala" sticker on the back of her phone. "Someone laughed and said, 'You're supposed to replace that with a Warren sticker.' And my view was, no, it's OK. It is a part of the energy that they bring to our team," Warren said.

She sees a lot of phones in the hours of selfies she takes on the campaign trail with supporters, which she says both keep her grounded and can be difficult, because people share their personal struggles and appeal for help.

Did she expect that when she thought about running for president?

"It has been better and worse than I thought it would be, simultaneously," Warren said.