So let's learn more about Ellison and why some Democrats think this relatively obscure congressman is their best answer to Trump.
The basics: Ellison was elected a decade ago to Minnesota's 5th District, which includes heavily Democratic Minneapolis.
Since coming to Congress, he's been a reliably liberal Democratic vote — he's campaigned on his opposition to the Iraq War and his support for universal health care, and he's been a vocal opponent of voter ID laws.
He's no Donald Trump: Ellison's biography could not be more of a stark contrast to the most controversial elements of Trump's message.
He's the first Muslim to be elected to Congress and one of only two serving in the House.
When Ellison was sworn in for the first time in 2007, he made national news for taking his ceremonial oath with a Koran — one once owned by Thomas Jefferson, which he borrowed from the Library of Congress.
Since then, he's been frequently called on to be a spokesman for his faith. (Ellison was raised Catholic, but converted to Islam in college.)
He was also the first black person to be elected to Minnesota's congressional delegation.
And he's from the Midwest, a region where Tump snuck up on Hillary Clinton. (Minnesota voted for Clinton, but for a state that hasn't voted for a Republican since 1972, it was surprisingly close: President Obama won the state in 2012 by nearly 8 percentage points. Clinton won it by 1.5 points.)
He's got progressive cred: Ellison is co-chair of the Progressive Caucus in the House, and he backed Sanders during the primary.
The Sanders and Warren wing is currently the loudest liberal voice speaking out after the election. Both are having an “I-told-you-so” moment with the Democratic Party, saying it should have focused on a more populist message if it wanted to reach the white working class voters that broke for Trump in higher-than-expected numbers.
Ellison, say liberals, is someone they trust to make the progressive wing of the party more mainstream. “There's a big challenge that people feeling really jilted by a party that tried to stop the nomination process before it began,” said Neil Sroka with the progressive Democracy for America. “He would be really helpful for that.”
But some moderates are skeptical that turning the party to the left will solve the Democrats' problems.
“It didn't matter what type of Democrat you were on Tuesday,” said Jim Kessler with the centrist Democratic think tank Third Way. “You were defeated. … every element of the party has to look in the mirror and reassess, and say ‘What can we do better?’ ”
He can handle the cable news circuit: Ellison has a reputation as a level-headed politician who won't shy away from a political fight or controversy. Perhaps the most famous example of this came right after his 2006 election. Conservative commentator Glenn Beck, then at CNN, asked Ellison if he could be politically incorrect for a second, then demanded to know: “Sir, prove to me that you are not working with our enemies?”
Ellison, without getting flustered, replied: “Well, let me tell you, the people of the 5th Congressional District know that I have a deep love and affection for my country. There's no one who is more patriotic than I am. And so, you know, I don't need to — need to prove my patriotic stripes.”
The media coverage from that conversation was largely favorable to Ellison. Beck later said it was “quite possibly the poorest-worded question of all time.”
As the Huntington Post pointed out, doing battle with conservatives on TV could be one of the most effective ways for Democrats to reach voters and reshape their party, since there are fewer of them in office to do it the traditional way. Democrats have the fewest seats at every level of governance since the Reconstruction Era.
Which brings me to my next point:
He could shake up what the DNC does.
At the heart of Ellison's sudden popularity among progressives is the opportunity to fundamentally reshape the role of the DNC.
Think of the office of DNC chair as it exists right now as like the chief operating officer of a company — someone focused on logistics like fundraising and coordination to help the party, while the top Democrat in power is like the chief executive — the person providing the vision.
But the current formula, progressive Democrats say, is largely broken. Democrats were so badly decimated on Tuesday they are a leaderless party. So why not let this official position become the visionary leader of the party. The chair could focus less on fundraising — if people are excited about the party they'll donate anyway, Sanders argued — and more about giving the nation a solution to its economic anxiety.
Ellison's colleague in the progressive committee endorsed that idea in an interview with The Post's John Wagner: “They have to be advocates, and not just conduits,” said Rep. Raúl M. Grijalva (D-Ariz.). “The DNC should be both an organizing tool and an advocacy tool.”
Correction: An earlier version of this post misstated the percentage Obama won Minnesota by in 2012. He won it by nearly 8 points.