“The two new primary polls out this afternoon don't show any negative fallout for Biden in the D primary from the Ukraine story.”
Tweets Nate Silver. I’m having trouble making a link to his tweet, but you can look at all the relevant polls here . Silver doesn’t offer any ideas about why Biden is holding strong. Maybe people aren’t paying so much attention to the Ukraine story. ADDED: In related news, there’s a poll of Republicans, reported at The Hill , showing very low awareness of what Trump’s Ukraine phone call had to do with Biden.