(CNN) A viral crowd surfing video. A massive -- and growing -- online support network. Steady polling progress. And a promise of "something big in store" for Thursday night's Democratic presidential debate.

The current reality of the 2020 presidential race is this: Aside from Elizabeth Warren (and her surge into second place behind Joe Biden), there is no candidate with more momentum and buzz than Andrew Yang headed into tonight's third debate.

Which is, if you stop and think about things for 30 seconds, a pretty remarkable statement. Yang started the 2020 presidential race as a total and complete unknown, having never run for elected office ever before. He was polling at 0% because, well, he was a total and complete unknown.

His platform -- focused on the dangers posed by our rapidly automating society -- was different than what any of the other candidates were talking about. His central idea to offer a $1,000 universal basic income to every person 18 or older in the country was dismissed as unworkable and crazy.

And yet, Yang will be one of the 10 candidates on stage in Houston for the third debate of the 2020 Democratic primary. He has outlasted much more established political figures like Sen. Kirsten Gillibrand (New York), Gov. Jay Inslee (Washington) and former Colorado Gov. John HIckenlooper -- all of whom have left the race amid fundraising problems and disappointing poll numbers.

And at least at the moment, Yang finds himself firmly in the second tier -- with Sen. Kamala Harris (Calif.) and South Bend Mayor Pete Buttigieg (Indiana) -- slightly above bigger names (in politics) at least like Beto O'Rourke and Cory Booker.

How? Good question, without an easy and obvious answer!

I do, though, have a few theories:

1) Yang is an outsider at a time when voters want outsiders.

2) Yang seems like a normal person who doesn't take himself too seriously. In the last 48 hours, he's tweeted about the dumbness of scheduling a debate on the same night as an NFL game and posted a video of himself shooting hoops (and dunking!) as a way to warm up for the Houston debate.

3) Yang explicitly ran his campaign online, understanding that the power of the Internet was the only way -- in the early days of his campaign -- for someone with a profile like his to raise money and organize. He has also, from the start of the campaign, cast it as a team effort; he is the face of the movement, sure, but he is not the movement.

4) He's talking about an issue -- automation and what it means to who we are and how we work and live -- that feels fresh, relevant and, most importantly, different than the same boilerplate stuff voters are getting from other candidates polling below Yang.

Regardless of the reason(s), Yang has struck a chord at least among some segment of the Democratic primary electorate. In the last six polls on the race -- as collected by Real Clear Politics -- Yang's support ranges from 2% to 5%. Which isn't great, except when you consider that those numbers are more than 14 of the other 19 Democrats still running for president.

To be clear: Andrew Yang is still a long shot. The most likely outcome is that he has hit his ceiling and will go no higher. But no one -- including me -- thought that Yang would even get to this point. Which means that predictions about where he will go from here seem like a fool's errand.

And if Donald Trump's victory in 2016 taught the political class anything, it's this: Never, ever say never.