On the heels of his New Hampshire primary victory this week and his second place showing in Iowa's chaotic and disputed caucus last week, Bernie Sanders is closing in on front-runner status in the Democratic presidential contest.

His success has prompted commentators to ask how this septuagenarian and widely-regarded curmudgeon—who isn't even a member of the party whose nomination he is seeking—can attract thousands of supporters at rallies and raise hundreds of millions of dollars. And he is doing this while fighting off the Democratic Party establishment, recovering from a recent heart attack, and refusing help from outside groups.

A sense of belonging

One key to understanding Sanders’ fundraising accomplishments, argues Washington Examiner writer Tim Carney, is that Sanders’ campaign is rooted in belongingness. “Bernie has a loyal donor base because they don’t feel they’re simply boosting a presidential campaign. They feel they’re joining a movement, a cause, or an army.” Political parties and campaigns are flush with idealism and patriotism and thus have always been a spring of identity and belonging.

The Sanders’ campaign, however, has been unlike any other in recent memory (and perhaps ever). He is capturing and spreading a feeling of belongingness more powerfully than his competitors, and this applies even to the small donor who is typically overlooked before the election and forgotten after it. As Carney writes, “Sanders seems to be the best—or maybe the original—when it comes to making small donors feel like they belong. And that’s because he’s the closest to actually meaning it.”

The proof is in the numbers. As of earlier this month, Sanders has raised more than $60 million in small individual contributions of less than $200. This comprises nearly 56 percent of all his fundraising to date. (Only one other current Democratic candidate in the race, Elizabeth Warren, cracks 50 percent.) An army of supporters have signed up to make monthly contributions to his campaign, and in doing so have been made to feel like they're part of something bigger than themselves. The campaign has already surpassed 4 million donations. And not surprisingly, the language Sanders is using on his website after his New Hampshire victory activates visitors’ longing to identify with the larger movement he has started: “Not me. Us. We won New Hampshire, and now the establishment is going to throw everything at us. So we need to be ready. Lots of people making small donations is the only way we’re funding this campaign. Can you add yours?”

Why this works

We all have a deep longing to belong to something bigger than ourselves, to be appreciated, heard, noticed, loved. The stale gruel of individualism and consumerism we have been fed for decades has left us malnourished and eager to escape the shackles of loneliness. We long to identify with a community, a familyeven a political campaign.

Regardless of political loyalties, the Sanders campaign can teach us something about how nonprofits can and should interact with their donors, large and small alike. They should ask them to be part of their community or movement. They should endeavor to strengthen their personal relationship with them. They should focus on their mission rather than their organization, and they should foster personal rather than transactional relationships with donors.

The key is having authentic rather than superficial relationships with your donors and inviting them to belong to the organization.

As Carney notes about the Sanders’ campaign’s success in attracting monthly donors, “This isn’t a transaction… It’s a relationship. And that’s something a lot of people are desperately seeking.”