Harry Reid , who died Tuesday at age 82, was not an especially well-known senator when then-Minority Leader Tom Daschle (D-S.D.) lost his seat in 2004. Daschles defeat propelled Reid to the partys top role in the Senate overnight.

To the extent that Reid had a national reputation at the time, it was as a relatively socially conservative western Democrat. Media coverage of his ascent tended to focus on the fact that he hailed from the then-red state of Nevada, supported some restrictions on abortion rights, and opposed most gun control measures.

A headline from the Austin American-Statesman was typical: Senates new minority leader breaking mold; Former boxer, Capitol Hill cop is no stereotypical liberal Democrat.

It came as something of a pleasant surprise, then, for the Democratic Partys progressive wing known in the 2000s as the netroots or online left when Reid became one of their foremost champions on Capitol Hill.

Reid was one of the earliest and most prominent Democratic lawmakers to view progressives as a key element of the Democratic coalition and cultivate a relationship with them. He identified with the lefts combative instincts, if not with every specific policy or candidate.

And his office became a storied training ground for staff who would later populate the most important progressive campaigns and offices. Alumni of Reids Senate office include Faiz Shakir, who managed Vermont Sen. Bernie Sanders 2020 presidential race; Ari Rabin-Havt, Sanders deputy campaign manager in 2020; Josh Orton, a top aide on the Sanders campaign; Kristen Orthman, a senior aide to Sen. Elizabeth Warren (D-Mass.) and a staffer on her presidential campaign; progressive activist and writer Adam Jentleson; Rebecca Katz, who advises insurgent progressive candidates; Mari Urbina, managing director of Indivisible; and progressive strategist Murshed Zaheed.

Progressives gravitated to him because he knew how to lead, said Katz, who was Reids communications director from 2005 to 2006. He didnt back down from a fight. He understood the Senate better than anybody. And he knew what was possible if you tried.

As a young alumnus of John Kerrys failed 2004 presidential campaign, Rabin-Havt came to Reids office looking to fight then-President George W. Bush. An opponent of the Iraq War with ties to what was then known as the progressive blogosphere, Rabin-Havt was initially skeptical of working for Reid, who he worried was too moderate.

Reid, a former amateur boxer, sold him on the prospect personally during the job interview. If you want to fight George Bush, so do I. This is the place to do it, Rabin-Havt recalled Reid telling him.

Notwithstanding Reids occasionally conservative stance on issues like abortion rights which he would later jettison his commitment to the Democratic Party s economic policies was forged in a childhood of extreme poverty in rural Searchlight, Nevada.

Reids father was a miner who suffered from alcoholism and died by suicide when Reid was a young adult. Reid nonetheless believed that the little material comfort his father had in his lifetime was thanks to his decision to join a labor union. And Reid, a convert to the Church of Jesus Christ of Latter-day Saints, told The New Yorker in 2010 that Social Security was the greatest social program since the fishes and loaves.

As a result, the extreme conservative domestic agenda of Bushs second term was tailor-made to unleash Reids inner prizefighter.