Toward the end of the 2020 presidential primary, Bernie Sanders and Elizabeth Warren were vying for control of the progressive lane to the Democratic nomination, and the tensions between their two camps were growing. When Warren dropped out on March 5, she declined to endorse her fellow senator. Adam Jentleson, a longtime hand in Democratic circles who was close to Warren, explained to The New York Times the key difference between the candidates: “She values the Democratic Party. She thinks it has flaws but is overall a force for good.”

But Sanders wasn’t going to take back his criticisms of the Democratic establishment to earn Warren’s support. Speaking to BuzzFeed, the Vermont senator’s deputy manager, Ari Rabin-Havt, fired back: “Bernie Sanders has had the same values for his entire career, and he isn’t changing that.”

The rivalry between the two senators and their teams had been heated. But a few weeks earlier, Jentleson and Rabin-Havt, along with Sanders senior adviser Faiz Shakir and other leading progressives like communications expert Rebecca Katz and Indivisible’s Mari Urbina, posed together for a friendly photo before a debate in Nevada. Although some of them were now political opponents, they were also all veterans of former Senate Democratic leader Harry Reid’s office, and the retired Nevada senator was at the event.

Today, Reid’s ex-staffers have leadership roles throughout the progressive movement. Rabin-Havt was Sanders’s legislative director until July; Shakir is still a senior adviser as well as the founder of the progressive media outlet More Perfect Union. Joshua Orton, another Reid alum who worked for Sanders as a senior adviser from 2018 to 2021, is now a senior policy adviser to the Labor Department secretary.

Jentleson, Reid’s former deputy chief of staff, is an author and an advocate for abolishing the Senate filibuster; he and Katz, formerly Reid’s communications director, run Battle Born Collective, a progressive messaging shop. Another former Reid communications director, Kristen Orthman, is now Warren’s deputy chief of staff; and Urbina, Reid’s former senior adviser for Latino and Asian affairs, is a managing director at Indivisible. These and other former Reid staffers, who call themselves “Reidworld,” are reshaping Democratic Party politics.

I’ve interviewed a number of these progressives over the past few months, and without exception, they told me that they’ve used what they learned from Reid—who led the Senate Democrats from 2005 to 2017—to help kick-start and strengthen the movement. But how did a moderate senator become perhaps the most influential mentor to the left wing of the Democratic Party? And what exactly did they learn from him?

Sex work was the main industry in Searchlight, Nev., when Harry Mason Reid was born there in 1939. Only a few hundred people lived in the town, and with no nearby churches, Reid told me recently, the closest his family got to one was the pillowcase nailed to a wall in their home reading: “We can, we will, we must reelect Franklin Delano Roosevelt.”

“That was my religion until I left,” Reid said.

There was also no high school in Searchlight, so as a teen Reid moved to nearby Henderson—a relative metropolis with a few thousand residents. He went on to attend Southern Utah University, where he converted to Mormonism, and George Washington University Law School. Then he returned to Nevada and worked his way up the ranks of state politics, from Henderson city attorney to lieutenant governor to gaming chairman, before winning a seat in Congress in 1982. By 1986, Reid had won his first election to the Senate, where he would serve until his retirement in 2017.

Reid’s approach to politics was to be “more of an insider, behind-the-scenes player, which is what made him effective as leader,” said Rabin-Havt. The blunt but soft-spoken senator was no leftist: He backed the death penalty, wanted to overturn Roe v. Wade, and voted for the invasion of Iraq. But he balanced those positions with liberal stances on domestic social programs, especially Social Security, which he fiercely defended throughout his career.

Reid eventually climbed to the top of his caucus, taking over from Tom Daschle in the wake of the devastating 2004 election, when George W. Bush was reelected and the Republicans won both chambers of Congress.

In December 2004, just as he was assuming the leadership of the Senate Democrats, Reid decided to hire Rabin-Havt as his online communications director—not in spite of the young man’s leftist politics but because of them. On the surface, Reid seemed an unlikely person to reach out to Rabin-Havt. But at a time when many other Democrats and Washington experts thought the progressive movement a fringe oddity, Reid understood the potential power of the party’s left wing.

The importance of hiring an online strategist wasn’t obvious 17 years ago. There was no Twitter or YouTube, and Facebook was in its infancy. But Reid wanted to harness the growing left movement within the Democratic Party. Sick of the Iraq War and of losing to the GOP, progressive Democrats were becoming increasingly angry about their party’s centrism. Reid wanted to direct that energy against the Republicans, but to do so he had to reach the left where they were: the blogosphere.

Including Rabin-Havt in the Senate Democratic Policy and Communications Center, known as the “war room,” helped Reid mobilize the party’s progressive base to his advantage. Less than two years later, Reid attended the inaugural YearlyKos conference—later renamed Netroots Nation—sponsored by the liberal blog Daily Kos. It was a savvy move that sent a message to the party establishment that the online left needed to be taken seriously as part of the Democratic coalition. Rabin-Havt told me that nobody “in the caucus was willing to open up to the online left before.”

But not everyone was on board with Reid’s plan to attend the conference and embrace progressive bloggers. According to Rabin-Havt, some Reid staffers urged the senator to use the opportunity to stage a “Sister Souljah moment” and decry the party’s left. (At a Rainbow Coalition convention during the 1992 Democratic primaries, Bill Clinton denounced the presence of the rapper Sister Souljah, accusing her of inciting violence against white people.) Rabin-Havt said he was apoplectic: “I was like, ‘Guys, these are the people funding your fucking campaigns. Are you really going to tell them to fuck off? That’s crazy. You don’t go to somebody’s house to insult them.’”

Reid agreed with Rabin-Havt and gave a speech broadly aligning himself—and, by extension, the Senate Democratic Caucus—with the online left. The speech became a turning point, Rabin-Havt said. From then on, Reid was able to count on the support of influential lefty bloggers.

Two years later, when the Democrats took both houses of Congress, it was clear that the online strategy had worked—for both the Democrats and grassroots organizations like MoveOn, a political action committee that began as a series of e-mail petitions. As Rabin-Havt recounted, “In the 2006 election, MoveOn raised like $30 million. Tom Massie, who was at MoveOn at that point, became a major regular figure on Capitol Hill with access to members. It was like a total change in nature. Bloggers were having conference calls and access with the Senate leader.”

Reid’s approach to politics and personal relationships helped him win over the nascent online left, but it also earned him the trust of his staff. The former senator told me he knew that he could hire for experience, education, and intelligence—but not loyalty. Katz said Reid won her over when she was filling in for his Nevada press secretary. The senator was giving interviews, calling reporters, and having Katz read their phone numbers to him. She kept stumbling over the digits, and Reid turned to her and asked if she had a learning disability. Katz, who is dyslexic, replied that she did, and she recalled that she felt ashamed at that moment. But then Reid looked her in the eye and said, “You must have worked twice as hard as everyone else to get where you are.”

That endeared him to her forever, she told me, and showed the values he prioritized in his staff. “He didn’t want people who had everything given to them,” Katz said. “He wanted people who went through and fought hard like he did.”

Mari Urbina told me that Reid’s retail approach to politics taught her the power of organizing. She entered Reid’s office as a student fellow in the summer of 2008 and left seven years later as senior adviser on Latino and Asian affairs. “My job,” she said, “was to make sure we were understanding the push and pull of how, legislatively, we were showing up in the communities. That could be part of someone’s job, but that was my entire job.”

Today, Urbina uses those skills as managing director at Indivisible, one of the largest progressive grassroots organizations. Chief among the lessons she learned was the idea of the “outside fight” and the “inside fight”—the difference in tactics when it comes to working with community groups versus working within political institutions. Reid respected “the different needs and interests people had,” Urbina said, “whether it was a Democratic caucus or it was having respect for the folks on the outside who were fighting.”

During Urbina’s time with Reid, Nevada’s Hispanic population was a growing electoral force. The senator “always made time to meet with Latino groups in the state and nationally and developed a strong press operation to reach out to the Hispanic community,” former senior adviser Jose Parra wrote me in an e-mail.

The commitment to immigration issues and Latino concerns was a change for Reid, who in 1993 said on the Senate floor that “no sane country” would offer birth-right citizenship to the children of undocumented immigrants. But as the demographics shifted in Nevada and the country, Reid committed himself to expanding the Democratic Party.

In 2010, Urbina watched Reid reach out to Hispanic groups and communities in his general election fight against Republican Sharron Angle. When Angle tried to use his support for immigrants against him, Reid embraced the attack, saying it showed, in his words, that he supported all Nevadans. By not waffling on his support for immigration reform during an election, he earned the trust of the state’s voters. Reid was reelected in a narrow 50.3 to 44.5 percent victory—proving the importance of working both within and outside political institutions to gain and hold power.

Even during that tough reelection fight, Reid wanted to mobilize the party’s left. In 2010, he hired Jentleson, an up-and-coming political operative, to help strengthen his relationship with the party’s grass roots. Jentleson told me that he expected the assignment would be a brief résumé-building experience. “I figured it was a great way to gain some experience, short-term gain, that he would lose, and I would probably go find some other job on the Hill,” Jentleson recalled. “But things turned out a little differently.”

Jentleson said he learned from Reid that politics can require taking hits in the short term in exchange for gains over the long haul. It was a strategy that Reid had perfected over his career. “That’s my philosophy about life,” Reid told me. “You can’t be afraid to lose.”

During the government shutdown in 2012, Republicans in the House, egged on by conservative senators like Ted Cruz, refused to compromise with the Democrats on a budget funding bill. It was an act of brinkmanship that led them straight into Reid, the Senate majority leader, who would not budge on demands from the Tea Party–dominated House.

House Republicans employed a clever tactic, sending mini-appropriation bills to the Senate for funding Head Start, the National Parks Service, and other popular programs. Reid and the Senate Democrats stood firm, initially drawing bad press for refusing to break the budget into pieces. It paid off. The GOP came back to the table on Reid’s terms after it became clear that the Democrats were willing to wait out the Republicans’ intransigence, and the two sides negotiated a compromise.

“To get an advantage strategically, you sometimes have to take hits to take a position that would eventually yield a strategic advantage,” Jentleson said. “Sometimes you had to absorb a few days of bad press coverage, and eventually, if you could make it through those few days—which never really matter that much in the grand scheme of things—you would emerge with an advantage.”

In 2012, Jentleson approached Faiz Shakir, who was working in the office of then–House minority leader Nancy Pelosi, about joining Reid’s team. Reid had asked Jentleson to recruit Shakir, because the two had worked together at the Center for American Progress. Shakir embraced the offer and would remain with Reid until the Democratic leader’s retirement; later he would become a senior adviser to Sanders.

Shakir described Reid’s office as one where disagreement and debate were welcomed. Reid wasn’t interested in hiring sycophants for his senior staff. Instead, he encouraged disagreement and wanted to hear from the different political groups vying for his attention—another example of how he welcomed a political strategy that embraced both the “inside fight” and the “outside fight.”

“Neither fight was a caricature,” said Urbina. “There was real relationship analysis, real power analysis; there was a real respect in understanding the different needs and interests people had.”

Shakir described the senator’s approach as “an old-school Democratic philosophy” based in the party’s New Deal era, when fighting for and being from the working class were seen as badges of honor. By hearing from members of his staff representing varied interest groups, Reid was able to consider the tactical advantages and disadvantages to his decisions both for his constituents in Nevada and the Democratic Caucus.

“Harry Reid essentially allowed us to kind of grow in our own directions,” Shakir said. “He wanted that. He was kind of like, ‘I like having people who can have ideological convictions and also have some differences of opinion between them.’”

In 2015, as the primary fight between Sanders and Hillary Clinton began, Reid asked Shakir what he thought of the Vermont senator. Shakir replied that he thought Sanders would be “formidable” and could give Clinton a run for her money. “I remember [Reid] saying, ‘I agree with you,’” Shakir recalled. ‘He’s going to be a strong candidate.’”

A few months later, Sanders and his team reached out to recruit Shakir. Reid gave his blessing and promised to hold his job for him. “I’m on Harry Reid’s staff, essentially helping Bernie Sanders through the end of ‘16 and ‘17 with his knowledge and awareness,” Shakir said. “It gives you a sense of how Harry thought about this. He had a respect for Bernie Sanders.”

Reid and Sanders were already friendly, having worked together for years. Reid told me that Sanders was “as responsible for my success in the Senate as any other senator.”

“He helped me do some very terrific things for the country,” Reid said, referring to the inclusion of funding for community health centers in the Affordable Care Act—an addition that was done at Sanders’s behest.

Sanders would lose the primary to Clinton, who then lost to Donald Trump. Shakir went on to work for the ACLU in 2017 after Reid’s retirement, but he kept in touch with Sanders, introducing him to Rabin-Havt. Three years later, the trio reunited on the 2020 Sanders campaign; Warren, who had already hired former Reid aide Kristen Orthman as her communications director, also had Jentleson by his side.

With Democrats controlling Congress and the White House, Reid’s former staffers have attained influential political positions on the party’s left, and they’ve been able to use and pass on the lessons they learned in the senator’s office, both from Reid and from one another.

“I do still have a closeness with my colleagues from day one, because they helped train me and they helped make me,” Urbina said. “And I feel a lot of gratitude for their insights and for their support and for the organizer that I am today.”