The problem is that the people who can get votes are the ones who would break away, but the people who control the money are the ones who would stay. You need both to get anyone elected.

Splitting the party would be a hail mary; you’d be betting that you could make enough in small-dollar donations from individuals to run successful campaigns and get people into office. And if you were wrong, you’d be leaving the second-most-powerful party in the country in the hands of people like Pelosi, Clinton, and Manchin–and burning the bridge behind you.

It’s not an impossible idea. In fact, it’s happened before (remember the Whigs?). But it’s a really tough road. I get why they’re leaving it as the last choice.