It very much looks like Biden is not going to be among the front runners in 2020, if he doesn't drop out completely. I think he's still popular among democrats who haven't followed the debates. He has to be doing pretty poorly among voters who have heard him speak in the last couple of years.

Apparently Trump thinks differently if he's trying to blackmail the Ukraine into producing dirt on Biden in exchange for military aid. I like the response from the head of the Ukrainian parliament. They're not known for twisting words over there:

“Clearly,” said Geraschenko, “Trump is now looking for kompromat to discredit his opponent Biden, to take revenge for his friend Paul Manafort, who is serving seven years in prison.” Among the counts on which Manafort was convicted: tax evasion. “We do not investigate Biden in Ukraine, since we have not received a single official request to do so,” said Geraschenko.
https://www.thedailybeast.com/ukrain...ial-us-request