America has a two party system. I don’t think there is much disagreement there. Most Americans are pretty entrenched in one of the parties. Every Democratic nominee for President from Bill Clinton’s 1996 campaign through Joe Biden’s 2020 campaign (seven elections) has received a minimum of 48% of the popular vote. Every Republican nominee for President from George W. Bush’s 2000 campaign through Donald Trump’s 2020 campaign (six elections) has received a minimum of 46% of the popular vote. Not every nominee from each party is a perfect match with every other, but one can probably venture 85-90% of the voting population has stuck with their party every time they’ve voted for President in this century. A very small sliver, single digits apparently, are up for grabs in any given election.
It would take a relative idiot to assume though that either party is a monolithic block. The last two Presidents have both polled below those 48-46% starting points in their terms, despite not underperforming in general elections. There is a clear separation in 2022 public polling between Joe Biden’s approval in swing states and the polling numbers of Democratic Senate and Governor nominees in those states. Donald Trump consistently polled below his ultimate outcome in both of his Presidential runs. There are clearly partisans in both camps unhappy with what their parties are giving them to vote for, but unwilling to vote for the alternative party.
The easiest way to understand the current Democratic Party’s divides is through the 2016 and 2020 primary battles between Hillary or Biden and Bernie Sanders. In 2016, Hillary Clinton beat Sanders 55.2-43.1%, or by 12.1%. Joe Biden beat Sanders 51.8-26.3%, or by 25.5%. If you awarded the “Sanders wing” the additional votes received by Elizabeth Warren and Tulsi Gabbard they get about 34.7% of the vote. If the “Biden wing” also gets the votes of Bloomberg, Buttigieg, and Klobuchar, they get 62.5%. For easy argument’s sake, the split averages out to 58.9-38.9%. The party is split 60-40 towards the more “establishment” wing of the party’s voters, which is why Joe Biden was able to be nominated with a more moderate, long voting record, while rejecting the “Green New Deal” and “Defund the Police.” The “bold progressive” wing of the Democratic Party that wants to change America is substantial, has the “activist energy,” and has a loud voice in the party, but they do not represent a majority within the party at this time, so they don’t win.
The best way to understand the Republican Party in 2022 is through the depths of the polling on Donald Trump. If you go through polling on the 45th President, his causes, and the issues associated with him, you find a floor of around 30-35% of the country. If you look back to his 2016 primary win, when his movement was in it’s infancy, Trump received only 44.9% of the vote. However if you combine his vote with that of fellow conservative firebrand Ted Cruz (25.1%), you get 70% of the vote. Trump/Cruz beat Rubio/Kasich by just over 2:1 in that process. Even when Trump and his issues and causes are at their weakest in polls, he keeps about two-thirds of the Republican 46% base in every Presidential race this century. The Trump base of the Republican Party is about 2/3 of the Republican Party. This is why their portion of the GOP tends to win Republican primaries against more “moderate,” “electable” Republicans that tend to be less “offensive.”
It’s very important to understand first and foremost that “Sanders wing Democrats” and “moderate Republicans” both overwhelmingly came home to vote for their party’s nominee in 2016 and 2020, hence why neither party underperformed in the results. Secondly, it’s important to remember that whatever small slice of left-wing Democrats Biden lost in 2020, or “respectability” Republicans bailed on Trump in either race, they both made up on the other end of their party by pulling in party skeptic voters. Third, it’s important to understand the Republican divide as mostly about style and stage craft (Was there huge differences on policy between Trump and Bush besides war?), and the Democratic divide as mostly being about how far the two wings want to go in implementing their ideals- Bernie and Biden both want to give more access to health care to the uninsured, they have different ways of “how.”
For a while, Joe Biden seemed to be able to float above the political divides. Before he ran for President in 2020 he seemed to have some good will from the “respectability” Republican wing. Despite running a primary campaign largely in opposition to stereotypes of the post-Obama Democratic Party, Biden never suffered the levels of scorn from “the left” that Hillary did. As President, that is all done. He was absolutely the only candidate who could have beaten Trump in 2020, and possibly in 2016 too. Today he is nearly universally hated by the Republican Party. The largest reason his approval is over 20% below his 2020 vote share is erosion in Democratic support. It’s more complicated than purely a run of Bernie voters rejecting Biden’s more “procedural” brand of politics, some of it is more “normy” Dems mad about gas prices and inflation too, but the mix is probably more the former.
In the Republican Party you simply cannot win most national and statewide primaries without at least sizable support from the more conservative activist base types. In the Democratic Party, you certainly can, but an antagonistic relationship with the progressive left base can sink you in a general election, just ask Hillary Clinton. Unfortunately for Joe Biden, he doesn’t get the only say on the matter. Whether he can actually do the things that Chuck Schumer and Elizabeth Warren call on him to do or not is clearly less important than the fact that they call on him for it. While Sanders has actually been a pretty decent team player in the Biden era, the fact remains that a third to two-fifths of the Democratic Party didn’t want Joe Biden, and they are blaming him and his style for everything they perceive as going wrong. In short, gravity remains a thing.