I think the analog to the Tea Party was the Sanders wing of the Dems. The Tea Party seems to have morphed or given rise to MAGA, and Sanders gave rise to today's progressives.I would add to this that, if Kamala Harris loses this election, it wouldn't surprise me in the least to see something similar happen to the Democrats. It's easy to forget that Bernie Sanders seemed to have a very real lead in the primary just 4 years ago. It wasn't until South Carolina (the 4th contest) that James Clyburn consolidated support around Joe Biden.
Here's how Biden had fared in the first 3 contests:
Iowa (caucus) - Biden came in 4th behind Sanders, Buttigieg, and Warren -- with 13.7% of votes cast.
New Hampshire (primary) - Biden came in 5th behind Sanders, Buttigieg, Klobuchar, and Warren -- with 8.4%.
Nevada (caucus) - Biden came in 2nd behind Sanders -- with 18.9% of votes cast.
And then he won 48% of the vote in South Carolina (Bernie was 2nd with 19.8%), mostly at the expense of the non-Sanders candidates.
Sanders continued performing well throughout the rest of the contests, although it soon became apparent that Biden would win the nomination. All told, Sanders got 26% of the votes nationwide.
Now, I'm not equating Trump to Sanders. But I would compare them in the sense that he would also represent a significant departure from the Dem party's norm. And I think Clyburn's action (along with actions by the DNC in 2016 to boost Hillary against Sanders) shows that the Dem PTBs realize this, too.
Could Dems be in store for their own "Tea Party" type uprising if Harris goes on to lose this election? If she wins, I think it's probably a moot question.
But in 2020, she went way, way left. So why would the progressives rise up--wouldn't it be the more moderate wing?