Sen. Bernie Sanders was endorsed by the comedian and podcast host Joe Rogan this week.

Sanders embraced the endorsement, which immediately led to criticism from progressives who view Rogan as bigoted.

Rogan has a massive audience, with the second most downloaded podcast on iTunes.

He's one of the biggest figures in media today.

Despite being divisive online, Rogan's broad appeal is a boost to Sanders' campaign and a sign he can appeal to the voters necessary to defeat President Donald Trump in November.

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Joe Rogan endorsed Sen. Bernie Sanders this week, prompting a flurry of online conversation — particularly after the Vermont senator embraced the endorsement.

Rogan, a comedian and podcast host, is one of the most prominent, influential people in the media world. But he's also a controversial figure who has offered a platform to conspiracy theorists like Alex Jones and made comments widely considered to be racist and sexist.

On Monday, Rogan had New York Times opinion writer Bari Weiss as a guest on his podcast and told her he would "probably vote for Bernie."

"He's been insanely consistent his entire life," Rogan said. "He's basically been saying the same thing, been for the same thing his whole life. And that in and of itself is a very powerful structure to operate from."

After Sanders welcomed Rogan's endorsement in the form of a tweet on Thursday, a number of progressives with blue check marks took to Twitter and promptly expressed disappointment and, in some cases, outright disgust.

But what's said about politics on Twitter is not necessarily representative of views held by the general public, and the fact remains that Rogan's endorsement could provide a huge boost to Sanders' campaign. It shows that despite being a self-declared democratic socialist, Sanders appeals to a wide base of voters.

Vox cofounder Ezra Klein tweeted on Friday: "Bernie's strength is that he can win over some voters who are skeptical of Democrats — like Joe Rogan. If you think getting Trump out of office is actually important, that's a good thing, and he should lean into it."

Millions of people listen to Rogan

Rogan has a huge audience. His official YouTube channel has 7.3 million subscribers, and his podcast — "The Joe Rogan Experience" — reportedly gets 190 million downloads per month, and it's been the second most downloaded podcast on iTunes for over two years. Rogan is not a mainstream media figure, but he appeals to a mainstream audience, with a wide array of listeners (primarily men) routinely tuning in to hear him and guests discuss everything under the sun.

A 2019 profile of Rogan in The Atlantic said: "He understands men in America better than most people do. The rest of the country should start paying attention ... Few men in America are as popular among American men as Joe Rogan. It's a massive group congregating in plain sight."

In this capacity, Rogan has the ability to put a different slant on Sanders' left-wing proposals compared with how they're often presented on cable news, which tends to look at the world via a centrist lens, or by right-wing figures who decry him as a dangerous socialist.

Sanders was on Rogan's show in August, and many of the comments on the YouTube video for the episode showed that listeners were genuinely surprised by what they learned. The top comment, for example, said, "I just realized that I allowed my opinion of this guy to be designed by everyone else. I actually like this dude." The video for the interview has been viewed over 11 million times.

Sanders is surging right now and could benefit from Rogan's endorsement

In 2016, Rogan voted for Libertarian candidate Gary Johnson, who had virtually no shot of winning the election. Sanders is in a far different position and stands to benefit far more from Rogan's support. He's been at the top of recent polls in early voting states like New Hampshire, is dominating the 2020 Democratic field in fundraising, and led the field in a CNN national poll for the first time this week. In short, Sanders is surging and has a legitimate shot of winning the 2020 Democratic nomination.

Recent polling on hypothetical 2020 head-to-head matchups also showed Sanders beating out Trump. Sanders was the only 2020 Democrat to have a slight lead over Trump in an Emerson College poll released on Friday.

Though Sanders is often characterized as someone who is too radical to win over voters beyond the progressive wing of the Democratic party, evidence suggests otherwise.

Sanders also has the highest favorability rating among 2020 Democratic candidates, according to a FiveThirtyEight analysis based on an average of national polls conducted from December 19 through January 15. The Vermont senator is viewed favorably by 73% of Democratic or Democratic-leaning voters. Comparatively, former Vice President Joe Biden and Sen. Elizabeth Warren, the other leading contenders, come in at 71% and 68%, respectively.

And Sanders' overwhelming popularity with young voters in 2016 has carried into 2020, with polling consistently showing him way ahead of the rest of the Democratic field with the demographic. With young voters participating in elections in increasing numbers — including a 16 percentage-point jump in participation among voters aged 18 to 29 between the 2014 and 2018 midterms — their support could prove decisive for Sanders.

When asked by Insider what motivated the Vermont senator to welcome the Rogan endorsement, Briahna Joy Gray, the national press secretary for Sanders' 2020 campaign, said, "The goal of our campaign is to build a multiracial, multigenerational movement that is large enough to defeat Donald Trump and the powerful special interests whose greed and corruption is the root cause of the outrageous inequality in America."

"Sharing a big tent requires including those who do not share every one of our beliefs, while always making clear that we will never compromise our values," Gray added. "The truth is that by standing together in solidarity, we share the values of love and respect that will move us in the direction of a more humane, more equal world."

It's too early to call Sanders the frontrunner, despite his recent surge in the polls. Biden has consistently been at the top of national polls for months, and neither Sanders nor Warren have been able to make a significant dent in his strong support among black voters — a demographic that has historically been crucial to winning the Democratic presidential nomination.

But there are increasing signs that Sanders is more electable than many mainstream commentators and analysts have acknowledged, including Rogan's endorsement.