Bernie Sanders may be a long shot for the presidency, but on liberal talk radio, he’s already king.

The Vermont Independent senator has for years been a fixture on the airwaves and internet streams of left-wing political talk shows, building a national audience eager to enlist in his populist crusade against the 1%. So when Sanders declared his dark-horse presidential bid last month, the response from talk radio listeners was overwhelming — and nearly unanimous.

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“For my audience, the core of the Democratic Party, it’s Bernie Sanders. There’s no question,” said Atlanta-based talker Mike Malloy. “It is very consistent. It is unwavering for Bernie Sanders. It’s consistent responses no matter where the calls are coming from.”

From local personalities to nationally syndicated and satellite radio heavy-hitters, interviews with nearly a dozen liberal talk radio hosts show Sanders is so far crushing the primary — at least when it comes to their medium.

“For my audience, the core of the Democratic Party, it’s Bernie Sanders. There’s no question.” Talk radio host Mike Malloy

Few people understand the pulse of the hardcore activist base better than the radio hosts taking calls and emails from listeners every day. They say their audience views Hillary Clinton skeptically (but would vote for her in a general election), and that listeners know next to nothing about Martin O’Malley, Jim Webb, and Lincoln Chafee, who are also considering Democratic presidential bids.

For Sanders, meanwhile, conditions are perfect.

While perpetually overshadowed by its far more popular conservative counterpart, progressive talk nonetheless reaches at least 20 million devoted listeners on radio and the Internet, according to Michael Harrison, the editor and publisher of Talkers Magazine, an industry publication.

Political talk radio listeners of all stripes tend to be more politically engaged and ideologically extreme than average voters, and thus more likely to vote in primaries. And the nature of the medium, which costs little to produce and is free to consume, lends itself to anti-establishment voices like Sanders.

“The default environment of radio is populist, is grassroots, is close to the ground,” Harrison said. Lately, commercial radio has gone through its most corporate phase in history, but it’s trending back towards “independent and populist talk,” Harrison added.

Like other left-wing audiences, talk radio listeners are looking for an alternative to Clinton. Massachusetts Sen. Elizabeth Warren is also very popular here. “My audience is pretty much in the ‘anybody but Hillary’ camp,” said Iowa-based Ed Fallon, who has fielded many pro-Sanders calls.

But unlike some other corners of the progressive movement, Sanders has put down deep roots in talk radio. “My audience has known Bernie for a long time. He’s been very accessible on radio for years,” said New York-based syndicated host Sam Seder.

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And as listeners have become increasingly convinced that Warren is not running for president, they’ve coalesced around Sanders.

“It has been 99% a love affair between Bernie Sanders and my audience,” said Boston-based radio host Jeff Santos, whose show can be heard in the presidential state of New Hampshire. “Since he’s announced, it’s been unanimous and incredibly impressive.”

Sanders’ most important relationship in liberal talk started in a living room in Montpelier, Vermont, after the 2003 invasion of Iraq. Thom Hartmann had just started broadcasting his show from there and booked Sanders, then the state’s congressman.

The lawmaker was such a hit with listeners that it was quickly decided he should have a regular guest slot. Dubbed “Brunch with Bernie,” Sanders essentially took over an hour of Hartmann’s show every Friday, expounding on the week’s news and taking calls.

“They’re over the moon for Bernie Sanders, they’re over the moon for Elizabeth Warren, but when you tell them they’re a narrow slice of America, they get really mad.” Syndicated radio host Norman Goldman

Hartmann now hosts the top-rated progressive talk radio show in the country, and Sanders still does an hour of “Brunch with Bernie” every week, more than a decade later.

Some on Sanders’ staff have questioned this use of the senator’s time, but Sanders enjoys it too much stop, an aide said.

When the senator announced his presidential bid, Hartmann quickly offered his endorsement and his listeners were eager to enlist. “I haven’t had a dissenting or skeptical or cynical voice about Bernie’s candidacy since he announced,” Hartman said from his studio, now in Washington, D.C., near the Capitol.

Sanders is also close with host Bill Press, another top liberal talker based in Washington. Press, a former chairman of the California Democratic Party, hosted some early Sanders presidential brain trust meetings at his Capitol Hill home.

“As a talk radio host reaching the progressive base every day, I have never seen the level of all-out excitement that I’ve heard from viewers and listeners in the last couple days,” Press said shortly after Sanders announced his run.

For the activists who consume liberal talk radio, the fact that Sanders has probably joined more picket lines than any other of Congress is a major selling point.

“The progressive radio audience is really excited to have Bernie Sanders in the race and feels he’s one of them,” said Ari Rabin-Havt, who hosts a morning show on Sirius/XM’s liberal talk channel. “You hear it in nearly every call on the presidential race since his announcement.”

That’s not true for other challengers to Clinton. “Martin O’Malley isn’t a known quantity to this audience at all. Jim Webb is not a known quantity,” said Rabin-Havt, echoing other hosts. “This audience knows and likes Bernie.”

This audience could be a valuable in a partisan primary, but even Sanders’ biggest fans acknowledge he has little chance of winning the Democratic nomination — let alone the White House.

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Still, they appreciate his ability to influence the debate. “I think the whole [disappointment with the] Obama presidency has sort of reoriented people to not be as focused on the intent or will of a specific candidate, but rather the different mechanisms to push them in a certain direction,” Seder explained.

But Sanders’ near-universal appeal among liberal talk listeners has made things awkward for hosts who approach 2016 more pragmatically.

Los Angeles-based syndicated host Norman Goldman, who thinks Sanders’ appeal is too thin, has engaged in daily battles with callers since the senator announced.

“They react like a betrayed lover. They act like I’ve been cheating on them,” he said. “They’re over the moon for Bernie Sanders, they’re over the moon for Elizabeth Warren, but when you tell them they’re a narrow slice of America, they get really mad.”

Fellow Los Angeles-based host Stephanie Miller, who supported Barack Obama over Clinton in 2008, is now with the former secretary of State. “I love Bernie Sanders, and I love all his ideas, I’ve had him on many times,” she said, but Miller doesn’t think he can win.

That alleged marginalization of Sanders has prompted some callers to threaten to stop listening to her to show. “Last time, I got called the Obama-loving Hillary-hater,” Miller said. “Now I’m the Bernie Sanders-hating Hillary apologist.”