Sen. Al Franken (D-Minn.), right, with Sen. Charles E. Grassley (R-Iowa). (Win McNamee/Getty Images)

Ever since Donald Trump won the 2016 election, people have been asking me who Democrats could — and/or should — put up against him when, presumably, he seeks reelection in 2020.

My rote answer goes something like this: Someone who is not a politician.

Why? Because Trump won by casting himself as the ultimate outsider to a political system that lots and lots of Americans — in both parties — hate. As a celebrity (and not a politician), Trump was held to a different standard of behavior, too. Things that would have ended — or badly handicapped — other candidates bounced off Trump with little damage done.

Nominate just another politician in 2020 and, I've believed, Democrats are playing into Trump's hands — allowing him to continue to run as an outsider and against a broken system despite the fact that he will have spent four years in the White House. Pick a Mark Cuban or Starbucks founder Howard Schultz, on the other hand, and now you are fighting Trump on equal terms.

A column Monday morning by National Journal's Josh Kraushaar made me rethink my insistence that Democrats would be best served by nominating someone who's never run for office. In the piece, Kraushaar writes the following about Sen. Al Franken of Minnesota:

He’s emerged as one of the Demo­crats’ most ag­gress­ive and ef­fect­ive ques­tion­ers of Pres­id­ent Trump’s Cab­in­et nom­in­ees. He’s gen­er­ated nu­mer­ous made-for-TV clips as one of the few Demo­crats will­ing to go full-bore against his party’s top tar­gets — Jeff Ses­sions, Tom Price, and Betsy De­Vos. He’s fi­nally show­ing some per­son­al­ity in the Sen­ate, punc­tu­ated by his laugh-out-loud ex­change with En­ergy Sec­ret­ary-des­ig­nate Rick Perry. And he’ll be one of nine Demo­crats on the Ju­di­ciary Com­mit­tee ques­tion­ing Trump’s Su­preme Court nom­in­ee, Neil Gor­such. This is Al Franken’s mo­ment in the spot­light, and if he chooses, he could par­lay his good for­tune in­to a bid for the pres­id­ency in 2020.

In the column, Kraushaar notes that Franken, once dismissed as the comedian running for the Senate, now has just the sort of résumé that makes him potential presidential material. Franken is a Harvard graduate. He's also a two-term senator who demonstrated an ability to win the very blue-collar Midwestern voters that Hillary Clinton could not in 2016. Franken won voters without a college degree by eight points in his 2014 reelection race; he won white voters without a college degree by four points. (Full Minnesota 2014 exit poll here.)

Kraushaar only touches on what I think is the most important appeal of Franken's candidacy: his celebrity. “In the age of Trump, be­ing a tele­vi­sion celebrity isn’t nearly the vul­ner­ab­il­ity that it once seemed,” Kraushaar writes.

I'd take it much further: I think being a celebrity (and a comic to boot!) — as Franken is from his days on “Saturday Night Live” — is a giant asset when running against Trump. And not only for the reasons I outline above. But also because Trump showed an ability and a willingness to attack on a very personal level in the course of the 2016 campaign — from “low energy” Jeb Bush to “Lyin’” Ted Cruz to “Crooked” Hillary Clinton. Who better to run against someone like that than a stand-up comedian who made a living needling people?

Need evidence of how well Franken can do this? Watch (or rewatch) his speech at the 2016 Democratic National Convention:

Now, Franken's most recent job is not as a comedian but as a senator. That could be a problem given how much people hate politics. But I can also see a scenario in which people want a celebrity and are drawn to someone who values frank talk but also, after four years of President Trump, value someone with a little bit of background in how the federal government works. Franken is a unique hybrid of entertainer and politician, if Democratic voters are looking for someone like that come 2020.

No one in the Democratic Party is totally sure what their voters want in a candidate or what sort of candidate gives them their best chance of beating Trump in 2020. If Trump has truly changed all political calculus as to how you run and win, however, Franken starts to look like a more appealing choice than anyone — including Al Franken — might have thought a few years ago.