because the DNC doesn't want a real candidate. They still don't even think Trump's a threat.
Both sides had 4 years to prepare. The GOP, as much as I loathe them, used those years well to develop a plan to destroy our democracy. The Democrats decided early on that they had 2024 in the bag, and have done nothing in the intervening years. They could have picked basically any Democrat and built up their candidacy for the last four years, they could have had a real primary with debates, but instead we've all been told to shut the fuck up and vote blue no matter who.
That’s the problem, isn’t it? Show me your idea of a real candidate and I’ll find you a bunch of Dems who would rather have Harris or stick with Biden.
There are a number of them being floated right now. If Biden had dropped out a year ago, they would've had a traditional competition in the primary. Then we would've all gotten complacent and assumed we had it made, and we'd end up in 2016 again.
But to directly answer your question, the names I see being floated the most are CA gov Newsom, MI gov Whitmer, KY gov Beshear, and PA gov Shapiro. And yes, switching to any of them would be difficult and risky.
Buttigieg is also brought up pretty frequently and while I'm not a huge fan of him he seems to poll better than Harris. Personally I'd prefer a climate focused candidate like Whitehouse but I know it's a hard sell to the establishment.