I almost posted this to Politics, but since it is a call to "The Left" couched in terms of the people of the U.S. Democratic Party (rather than to its leaders), I thought it might be more suitable to Socialism.
In addition to talking about Project 2025 and the need to fracture the coalition that wants aristocracy, Doctorow writes this:
What's more, there's a much stronger natural coalition that the left can mobilize: workers. Being a worker – that is, paying your bills from wages, instead of profits – isn't an ideology you can change, it's a fact. A Christian nationalist can change their beliefs and then they will no longer be a Christian nationalist. But no matter what a worker believes, they are still a worker – they still have a irreconcilable conflict with people whose money comes from profits, speculation, or rents. There is no objectively fair way to divide the profits a worker's labor generates – your boss will always pay you as little of that surplus as he can. The more wages you take home, the less profit there is for your boss, the fewer dividends there are for his shareholders, and the less there is to pay to rentiers
The alternative to a worker-led Democratic Party is a Democratic Party run by its elites, whose dictates and policies are inescapably illegitimate. As Hamilton Nolan writes, the completely reasonable (and extremely urgent) discussion about Biden's capacity to defeat Trump has been derailed by the Democrats' undemocratic structure.
To limit Biden's harms, leftists have to take over the Democratic Party and the progressive movement, so that he's hemmed in by his power base. To limit Trump's harms, leftists have to identify the fracture lines in the right coalition and drive deep wedges into them, shattering his power base.